Hemp and Cannabis Integrated and Organic Pest Management


Assassin Bugs, An Organic Hemp Cultivator's Helper

DIY Raptor Perches for organic hemp pest control

Organic Spotted Bee Balm Cuttings, Parasitic Wasps and Organic Hemp IPM

Birds and Native Plants, An Organic Hemp Grower Partnership

Organic Hemp Cultivation and Pest Control, Documenting Weather Patterns

Ecosystem Matrix Tools for Organic Hemp Cultivation and Pest Control

Prescribed and Simulated Burning Importance

Birds, an Important Part of Organic Hemp Cultivation

Hemp IPM & Tent Caterpillars

Hemp on Green Roofs

Cleanliness (OIPM) Pest Control

Painted Lady Caterpillar and Butterfly Management


Assassin Bugs, An Organic Hemp Cultivator's Helper

 Assassin bugs are a great pest control partner to have when growing hemp organically.  

Milkweed assassin bug, Zelus longipes, is an important part of an organic hemp pest management program

Members of the Reduviidae insect family, assassin bugs are the perfect hemp (or for that matter any organically grown garden plant) pest predator. They inject a digestive secretion into their prey and then suck out their prey's body fluids through a straw-like snout.  Assassin bugs favorite hunt includes; aphids, beetles, caterpillars, leafhoppers and even bees and flies.

Included with the Assassin bugs in the Reduviidae family are the closely related ambush bugs (subfamily Phymatinae), wheel bugs (Harpactorinae) and kissing bugs (Triatoma spp.).  Some Reduviidae can and will bite humans.  As with any insect bite,  a bite from these insects may be painful and proper first aid should be administered.

Foraging across the garden, the assassin bug's appetite is voracious and non-discriminatory, devouring both bad and beneficial insects.  But on the whole, the assassin bug is welcomed as an eat all pesty pest bug control partner. 

Milkweed assassin bug, Zelus longipes, foraging on Monarda punctata

The key to managing the assassin bug in the hemp growing area includes the use of nectar producing native plants the bug is naturally attracted to.  Strategic plantings of spotted bee balm, milkweed, goldenrod, mountain mint and other wildflowers can direct assassin bug's attention into those areas needing urgent pest control attention.

There are about one hundred fifty species of assassin bugs.  One of the most common assassin bugs seen in the garden is the Milkweed assassin bug, Zelus longipes.  

Milkweed assassin bug, Zelus longipes, have a never ending appetite for hemp cultivation pests

 The photos above are of a Milkweed assassin bug foraging across one of Arendell Hill's spotted bee balm, Monarda punctata, plants.

Though assassin bugs may look wicked, they can help the organic hemp grower keep pest insects to a minimum.

The native plants mentioned are known to attract assassin bugs looking for high-energy packed nectar.  Organic hemp integrated pest management will always use assassin bug attracting native plants around growing areas, either as permanent plantings or in movable growing containers for spot pest control.

The organic hemp nursery is a dynamic site, rich in complex ecosystematic matrices.  The relationships between native wildflowers, the Reduviidae family of insects and the hemp farm are important for the grower to understand.

Welcoming these colorful but alien looking bugs is another key component in a successful organic hemp growing program. 


DIY Raptor Perches for Organic Pest Control

Arendell Hill has two new raptor perches now and we hope the birds of prey make themselves at home on the fourteen feet tall bird stands. These raptor perches are inexpensive and easy to build, and can be moved as necessary to different locations in the future.

Organic Hemp Cultivation incorporates birds as pest control partners.  Here is one of two raptor perches at Arendell Hill.

The horizontal perch section is a 1 1/4" diameter wooden dowel and is fastened to the vertical support pole.

Raptor perch, horizontal wooden dowel attached to vertical metal support pole

The materials list is for two perches:

  • Three 10' galvanized chain link fence top rail posts for vertical support
  • One 4' in length 1 1/4" diameter wooden dowel for horizontal perch
  • two galvanized chain link fence 1 3/8" T connectors 
Raptor Perch materials, IPM for Organic Hemp Cultivation

The tools I used to construct the raptor perches included; a fence post hammer (so much easier than a sledge hammer), level, portable ratchet, metal screws and portable screwdriver.

Raptor perch support pole should be plumb vertical

I cut one of the three ten foot top rail posts in half and drove the smaller diameter end into the ground using the pipe hammer approximately three feet or depending on the soil composition deep enough to keep the five foot pipe section sturdy.

Using the level I made sure the support pipe I was driving into the ground was vertically plumb, straight up and not skewed or leaning to the side.

Raptor perch support poles are fastened together and secured with metal screws

Once the support pipe is hammered into the ground then the small diameter end of the uncut ten foot six inch top rail pipe with the wooden dowel attached are placed into the support pipe. The two vertical pipes are fastened together with two metal screws.  A pilot hole can be drilled for the two metal screws.

Because the raptor perch support post is not permanently anchored in concrete, it can be moved depending upon hawk or other raptor flight patterns.  Disassembly is easy; unscrew the two metal screws, remove the longer top rail with perch attached then pull up the support pipe hammered into the ground.

Birds of prey such as both the red-shoulder and red-tail, swallow tail kites, sharp-shinned hawks, Cooper's hawks, broad-winged hawk, Swainson's hawk, Screech owls, Barred owls, Great horned owls, Barn owls, Peregrine falcons, Kestrels and even vultures scour hemp cultivation areas for rodents and other vermin.

Rats, mice and other vermin will eat hemp and cannabis plants and flower buds for food and also for the phytochemical action upon their bodies. Once a vermin devours enough cannabis flower they make an easy target for a nearby bird of prey.

Raptor perches afford the birds of prey a reason to stop and check out the hemp farm.  For the grower, hawks and owls are an important part of the beneficial organic pest control team.


Why Monarda is a Great Organic Pest Control Partner

Monarda punctata, spotted bee balm, is a native wildflower here in Florida and an important pest control plant at Arendell Hill.  Spotted bee balm attracts beneficial pollinators and wasps and beetles, such as native ladybugs. Spotted bee balm also serves as a decoy, diverting pest bugs away from hemp crops.  Seeking out Monarda's nectar, potential pest insects soon find themselves consumed by lady beetles, dragonflies and other insects foraging in the bee balm.

Organic Hemp IPM Incorporates Spotted Bee Balm, Arendell Hill Nursery

December, with its cooler and shorter days here in Florida is the perfect time to root cuttings.  I cut six to eight inch healthy stem tips from a thriving bee balm plant and place the cuttings in a 72 count seed tray filled with a mixture of perlite, vermiculite and rockwool.  Cuttings are placed in a shade house and misted every twenty minutes for ten seconds.

Organic Pest Control Plants; Monarda cuttings root easily without hormones

That is it.  In two to three weeks the cuttings are rooted and ready to be potted up into four inch pots filled with an organic potting mixture.

Moreover, a very important benefit of incorporating Monarda punctata into a native plant based organic pest control management plan for the hemp garden is the plant's ability to attract the predatory sand wasps!  Sand wasps are highly effective at controlling hemp damaging marmorated stink bugs.

A stink bug infestation can quickly devour much of a hemp crop in short time.

Fortunately sand wasps love to feed their larvae stink bugs.  Sand wasps are a group of predatory wasps that include the Astata and the brightly colored Bicyrtes species.  Sand wasps seek out the nectar of Monarda, mountain mint (Pycnanthemum spp.) and milkweeds (Asclepias spp).  Adult sand wasps especially love to hone in on the odor of marmorated stink bugs.

Mamorated stink bugs, Halyomorpha halys, are an exotic pest native to the far east but now widespread in North America.  These pests can inflict significant damage on hemp crops as well as cannabis and other agricultural plants.  Yet sand wasps will kill these stink bugs and carry their bodies into tunnels in the ground to feed wasp larvae where they live during maturation.

A single sand wasp may kill dozens of stink bugs across the hemp cultivation area, greatly reducing  potential pest damage risk.

Organic Hemp Pest Control involves many native plants, like Spotted Bee Balm which attracts beneficial insects

Spotted bee balm is also one of the most carefree and easiest native plants and wildflowers to grow, requiring little if any attention while being resilient to salt, wind and drought.

Native plants are often ignored when integrated pest management programs are developed for organic hemp cultivation, yet native plants offer so many benefits to the hemp and cannabis grower.  Just as Monarda punctata attracts the stink bug killing sand wasp, other native species too play host to insects, amphibians, reptiles and birds that work together as an efficient team, keeping ecosystem balanced and effectively reducing pest pressures on crops.


 Last post we discussed the important roles wild birds have in organic based pest control for hemp cultivation.  

Ruby throated hummingbird, Archilochus colubris attracted to the many native plants of Arendell Hill Nursery, feeds on nectar & tiny insects
Today's post will consider what the hemp grower can do using native plant species to attract and manage birds interactions with the cannabis farm.

As we previously read, a wild songbird partnership begins with native plant landscaping.  Birds have always sought out native plant species for foraging, communal and safe harbor habitat.  Native plant species are their first choice when they are deciding to take up residence on a site.  This also holds true for raptors and migratory birds.  The connection with native plants lies deep within all birds DNA, a quid pro quo arrangement formed during earth's deep time.

Certainly non-native horticultural type plants may be popular and even attractive, however they do not offer the level of wild bird provisions afforded by native plant species.  This is a proven fact.  Moreover, non-native horticultural plants may also provide unwanted hemp pests a place to proliferate and do harm to native plant species through hybridization and even DNA alteration.  

Many non-native plants can quickly spread across the landscape, their seeds dispersed by winds, wildlife and human activity.  An organic hemp farmer will need to be able recognize invasive plants, such as Coral Ardisia, Ardisia crenata, or air potato vine, Dioscorea buldifera  and implement control actions to stop the non-native's spread throughout the hemp agriculture site.

Importantly, one of the keys to high terpene content in flower buds of any variety is a high level of biodiversity and complexity in the surrounding ecosystem matrix.  Non-native species reduce biodiversity, sometimes drastically.  The coral ardisia and air potato vines mentioned above are one particular threat to hemp farms because invasive plants can quickly displace hundreds of native plant species that previously existed within the hemp ecosystem matrix depleting biodiversity and throttling production of complex terpene expression in hemp flowers.

Complexity of terpenes in hemp due to biodiversity is what makes a flower special.  When a flower is desirable to the consumer, demand and sales increase.  High quality hemp is the goal of most growers.  By attracting cultivation site songbirds and planting a diverse landscape of native plants the grower gains more control over unwanted pests and also increases the quality of the hemp product by keeping cultivation site biodiversity high.  The songbird-ecosystem matrix complexity-terpene-hemp plant relationship is a very important grow optimization concept for the farmer to explore. 

History is full of examples of plants providing humans with amazing phytochemicals, substances rich in healing properties.  For instance, yaupon holly, Ilex vomitoria contains caffeine and many terpenes too.  Songbirds love to eat holly berries.  Yaupon also provides a home across its bark for countless different species of lichens and mosses.  Older yaupon plants support a complexity of fungi and mushrooms.  All of these ecosystem variables; the fungi, the lichens, mosses, birds, plant and wildlife litter interact together to help form a web of ecosystem matrix diversity that is essential to comprehensive terpene creation in hemp and other plants.

Native plants have evolved over the ages alongside soil formation, fungi & lichens, plants, weather trends, insects, birds, fish, lake, river and stream creation and flow, climate changes and other biological and geophysical factors. The ecosystems we are a part of today were fashioned and shaped through millennia, a result of 'trial and error' over vast expanses of time.

Native ecosystems are the product of natures long term refinement processes.  In fact the time factor nature has invested into forming the ecosystems around us is so vast that it is practically impossible for us to comprehend what has taken really place.

The result of these evolutionary process can be witnessed in the precisely balanced interactions associated with native ecosystems.  Natural checks and balances keep seasonal life cycles functioning smoothly.  This way no one or two life types becomes over abundant or out of control. 

So for the hemp farmer, outdoor growing can expose hemp plants to geophysical and biological variables that may activate both biological and epigenetic process resulting in increased terpene production and diversity. Many terpenes important to humans for cosmetic, pharmaceutical, agricultural and food purposes are synthesized by plants as responses to outside influences, or ecosystem variables.  Some of these may be related to the ecosystematic complexities surrounding presence of native plants, insects, fungi, birds and wildlife.

A strategically designed native plant filled landscape not only provides the basis for increased terpene development but also serves as the foundation for organic integrated pest management purposes.

Once native flora is established, birds will make themselves at home and begin to assist in managing insect populations.

I've found the following native plant species to be especially helpful in recruiting songbirds, raptors and other wild birds.

Shrubs and small trees:

  • Wax myrtle, Morella cerifera
  • Yaupon holly, Ilex vomitoria
  • American holly, Ilex opaca
  • Gallberry, Ilex glabra
  • Elderberry, Sambucus nigra
  • Firebush, Hamelia patens
  • Beautyberry, Callicarpa americana
  • Hoptree, Ptelea trifoliata
  • Coontie, Zamia integrifolia
  • Red mulberry, Morus rubra
  • Seagrape, Coccoloba uvifera & Pigeon plum, C. diversifolia (cold tender)
  • Groundsel tree, Baccharis halimifolia
  • Paurotis palm, Acoelorraphe wrightii (cold tender)
  • Coco plum, Chrysobalanus icaco (cold tender)
  • and many more.
Native tree species to plant for birds are:

  • Oaks, such as;
    • Live oak, Quercus virginiana
    • White oak, Quercus alba
    • Myrtle oak, Quercus myrtifolia
    • Shumard oak, Quercus shumardii
    • Swamp chesnut oak, Quercus michauxii
    • and many more
  • Red maple, Acer rubrum
  • Hickory, including
    • Mockernut hickory, Carya tomentosa
    • Pignut hickory, Carya glabra
    • Black walnut, Juglans nigra
    • and others
  • Magnolia, Magnolia grandiflora
  • Black gum, Nyssa aquatica
  • Cypress, Taxodium distichum & T. ascendens
  • Pines species:
    • Sand pine, Pinus clausa
    • Slash pine, Pinus elliottii
    • Spruce pine, Pinus glabra
    • Longleaf pine, Pinus palustris
    • Loblolly pine, Pinus taeda
  • Sabal palm, Sabal palmetto
  • Sycamore, Platanus occidentalis
  • Tulip popular, Liriodendron tulipifera
  • Silver buttonwood, Conocarpus erectus
  • Mangroves;
    • Black mangrove, Avicennis germinans
    • Red mangrove, Rhizophora mangle (cold tender)
    • White mangrove, Laguncularia racemosa (cold tender)
  • and so many others
Native plant societies, wildflower associations, local agricultural extension agencies and native nursery business associations are all excellent information resources on what species to use and how to plant and care for native plants.

Here in Florida, the following entities can provide important growing info about native plants;
Hemp farm landscaping should always be included during initial hemp growing planning considerations. Native plant focused landscapes should be installed concurrent with any hemp cultivation efforts.

The organic hemp farmer needs all available help with pest control.  Hemp agriculture will demand significant amounts of time from the grower.  Native plants can serve as hosts to nature's own great pest control specialists.


Organic Hemp Cultivation and Pest Control, Documenting Weather Patterns

 Some of the most informational variables the organic hemp farmer can record and analyze are weather patterns impacting the growing area.

Weather patterns are often predictive of pest outbreaks.  Droughts, floods, excess heat or cold, humidity levels, solar radiation, geomagnetism and barometric pressure fluctuations can trigger pest population explosions and also initiate certain pest activities.

Temperature changes, such as prolonged heat waves may cause insects to become much more active.  Insects are cold-blooded (poikilotherms) organisms, meaning their body temperatures fluctuate with outside temperature variations and heat is not generated internally through biological processes.  Prolonged heat waves can fuel insect activity due to increased body temperatures.

Some have estimated that for each two degrees Fahrenheit rise in temperatures over normal ranges, pest insects may inflict ten to twenty percent more damage as their metabolism and body temperatures increase.  These observations suggest climate change could have serious impacts on hemp organic integrated pest management as well as for other agriculture product pest management systems.

Droughts too may trigger prolonged insect feeding activities as bugs search for water sources within plant buds, stems and leaves.  During droughts, hemp and cannabis pest insects may be driven to eat plant matter in search of moisture.  Regular precipitation measurements may provide the hemp farmer with patterns that help predict pest activity.

Organic Hemp Pest Control, Ambient Weather wifi enabled rain gauge

Climate and weather patterns can also be helpful in determining which beneficial insects, or pest predators are most productive in an organic pest control role under certain climate conditions.  Abnormal weather patterns such as drought, extreme temperatures, winds and humidity levels may actually work against beneficial insects and favor hemp pests.

There are many low cost, reliable weather stations available today that monitor, record and summarize growing area weather variables.  Ambient Weather, La Crosse Technology and Davis Instruments are a few of more popular retail available weather instruments.

Organic Hemp Cultivation, IPM methods, Ambient Weather Station

I use an Ambient Weather ultrasonic unit that measures temperature, relative humidity, wind speed, barometric pressure, sunrise and sunset hours and other important ecosystem geophysical variables.  The Ambient Weather station was inexpensive, easy to set up and summarizes weather trends over time.

Most of the small personal weather stations also provide the capabilities to connect to the internet, allowing for participation in crowd sourced weather data sites.

Weather and climate data are an important but small part of a hemp cultivation site's ecosystem variable population.   

Our agrarian ancestors understood the importance of understanding weather patterns.  Their food growing efforts depended on weather systems knowledge.  They watched and listened to the clouds, birds, animals and other tell-tale signs of impending climatic events.

Organic Hemp Pest Control, Ambient Weather data display

Today, the hemp farmer must also be able to comprehend meteorological impacts on crops.  A daily log of cultivation site weather data provides so much important information.

A thorough understanding of geophysical weather variables driving much of the hemp farm's growing parameters will support successful organic cultivation efforts.

The successful hemp cultivator will use all available organic-based integrated pest management tools.  Weather recording systems are a critical part of any organic IPM program on hemp farms.


Ecosystem Matrix Tools for Organic Hemp Cultivation and Pest Control

 In the last several posts we've introduced the concept of ecosystem matrices into our discussion of organic integrated pest management (OIPM).  A balanced ecosystem exists when all of the many existing biological and geophysical entities are functioning in equilibrium with themselves and each other.  This seamless functioning forms the basis of an organic integrated pest management approach for the hemp farm.

Balanced ecosystems function efficiently.  Throughout deep time nature has refined how ecosystems work so that all life within an ecosystem has a place, function and role to play.  Within the biological and geophysical parameters of a balanced ecosystem, all life forms carry out predictable, functional duty.  Change does occurs but in a measured sense.  Functional ecosystem homeostasis is usually maintained on a rolling basis.

However, when the ecosystem becomes unbalanced some life forms may become overly dominant, consuming and damaging to other ecosystem entities.  Hemp farm pests such as certain caterpillars for example may play an important role in a balanced ecosystem yet in the absence of normally present control factors and predators, such as fire or birds, may experience such a rise in population numbers that they disrupt the predictable garden homeostasis and cause uncontrolled damage to crops.

The key to maintaining ecosystem homeostasis begins with an understanding of the hemp growing areas' biological and geophysical dynamics.  What fungi, plants and animal live on and use the hemp farm land? What are the typical weather trends including rainfall amount and wind characteristics?  What is the soil comprised of? How is the air quality? Every life form and geophysical variable that interacts with other farm life forms and geophysical parameters becomes an important part of the ecosystem matrix flux.

A good start to understanding ecosystem matrices begins with a list of what exists and what is happening across the growing area.  A hemp farmer who has a good understanding of his or her farm's ecosystem matrix should be able to jot down a relatively comprehensive bullet list of their garden's parameters .  This list will represent the existing site variables.  The existing state is a reflection of the site in the present moment.  The list  of existing site parameters will usually be somewhat different than the site's historical, or intrinsic list of what has previously existed and happened across the site previous to human development impacts.

This list should evolve into an ongoing effort in identifying the hemp farm's ecosystem variables, much like a diary.  The process of journalling identifies plants, animals, insects, weather conditions, sunrise and sunset times, weather events such as snow, rain and wind, and other variables.  The hemp farm ecosystem matrix variable journal can be developed over time by notation of observed variables into a notebook, on a phone or the computer.

The hemp farm journal will become more and more accurate and comprehensive over time as documentation accumulates.  Certainly collection of data requires a focused effort.  Day in and day out the hemp farmer must record what they encounter during the day.  Often, the most seemingly insignificant events can many times be the trigger that exerts influence over pests.  Many times these trigger events can go unnoticed, all the while supporting an increased pest presence.

As the amount of information in the journal grows, the usefulness of the data increases.  For me, the key to understanding volumes of hemp farm journal data is found in how the data is presented.  The journal's daily entries need to be arranged in a visually coherent manner to be most relevant and useful.  Once the raw data is compiled into a logical presentation, relationships between pest damage and ecosystem matrix variables can be more easily identified.

Although any collected data can be useful to the hemp farmer, a comprehensive journal will contain a minimum of one complete years observations.  A multi-year hemp growing journal will contain invaluable information that can provide important tools to the grower.

There are several approaches to organizing hemp farm existing matrix variables.  Table format is one way and graphs are another approach.  As a visual learner I do best with data arranged in graphic presentation.  There are any number of ways to arrange hemp farm ecosystem matrix data and while developing the existing ecosystem matrix variable list it is worthwhile to also research what the site's historical (intrinsic) ecosystem matrix might have been like.  Sometimes, on non-disturbed high quality successional or native forest sites there will be few differences between the existing ecosystem matrix or matrices and the intrinsic, historical ecosystem matrices. 

Across farmed, agricultural or in disturbed urban garden sites the existing and historically intrinsic ecosystem matrices will differ.  As there will usually be a number of remnant matrix variables still interacting on disturbed sites, it will be important for the hemp grower to have a broad understanding of both the intrinsic and existing ecosystem matrices on their cultivation plot or greenhouse.

Knowledge of how the growing plot evolved on a historical basis and how the land functions today will allow the hemp grower to quickly assess trends, those beneficial to desired plant growth and those detrimental to the hemp crop (or any other organically grown crop).

A highly successful Organic Integrated Pest Management System must be based in comprehensive knowledge of how the growing area functioned as an ecosystem in past times and how the farm's present ecosystem variables interact.

With this knowledge the grower can hopefully begin to manage ecosystem matrix variables with organic based approaches.  The finest hemp plants may be grown this way, without toxic and industrial chemicals.  The beauty of organically grown plants encompasses so many health and quality benefits, always appreciated by both the consumer.

How you depict your ecosystem matrix depends on what table, illustration, chart or list works best for you.  Each grower will have their own method.  The important fact is that the grower understands that the cultivation site possesses a historical (intrinsic) set of ecosystem variables which have evolved over time into the unique matrix of today.  

A grower who understands how their intrinsic and existing ecosystem matrices function will produce the very best organic agriculture product with minimal pest pressure.  Organic integrated pest management must begin with this broad understanding of site dynamics.


We encourage birds to make themselves home here in the Arendell Hill nursery gardens.

Wild birds, song birds, raptors and more.  Winged creatures serve an important part of our Organic IPM

I consider birds to be better than 'human help' at picking caterpillars and other potential pest insects out of our gardens.  Songbirds can keep the ground and shrubbery around a hemp cultivation area significantly free of larvae that are crawling around looking for leaves or flower buds to chew on.  Larger birds also, like red shouldered hawks here are vigilant in keeping the nursery free of disease vectoring rodent populations. 

Winged creatures have a definite advantage over crawling pests.  Winged predators can conduct reconnaissance across a ground area much quicker than most crawly pests can escape.  It is true that many insects can fly and are beneficial in their own ways, such as for pollination.  The advantage however lies with birds though due to their size, advanced development of senses and ability to quickly forage across large areas of garden.

Maintaining quality bird habitat for hemp farms should include practices that ensure ample bird forage provisions exist.  Feeders are one obvious way to attract birds and work well in creating a basic Integrated Pest Management program.  Yet bird feeders are just a start.  Native landscape plants that flower, fruit and produce seed are another worthwhile addition to bird feeders in hemp cultivation areas.

Importantly, once the grower begins to attract birds to their hemp growing area and the birds begin their caterpillar and pest insect control duty, the grower must also ensure that the farm provides a place for the birds to 'stay' and nest.  Communal habitat is best established by planting native landscape and wildlife value shrubs.  

American holly, Ilex opaca, provides forage and evergreen communal habitat to wild songbirds and as such can be an important part of an Organic Hemp IPM program. 

Native shrubs, rather than horticultural imported shrubs, will always be a wild songbird's and raptor's preference, for the native shrub's habit and familiarity are transcribed by countless previous generations into a bird's DNA.  Simply put, the wild songbirds are attracted to those native shrubs they and their ancestors have always lived in and around.   

It is true that some non-native horticultural shrubs and plants will also be utilized by wild birds.   However the net benefit to the hemp farm efficiency matrix will be reduced when using non-native landscape species.  In fact, it is possible non-native landscape plants can cause significant ecological systems damage.  When the growing ecosystem matrix becomes unbalanced pest pressure will increase.

As we will see in other posts, not only do native plant species support all important bird populations across the hemp farm, but native plant species also provide a number of other important pest control and nursery management functions.

We will also discuss in future posts, how to visualize the hemp farm bio-geophysical ecosystem matrix.  Though the name 'bio-geophysical ecosystem matrix' may sound complex, the concept is a simple one.  Everything affecting the hemp farm makes up the matrix.  There are many variables, such as birds, wildlife, rain, wind, temperatures, pests, soil, water and others.  The way these variables act upon and influence hemp plant growth in the garden is what the matrix is all about.

Another term I like to use when thinking about the ecosystem matrix is the phrase 'Languages of Nature'.  Each variable asserts an influence, good or bad, on the hemp plants.  Each good or bad influence can be known through interaction with our senses.  Ecosystems communicate the effects of most impacts they experience through measurable responses. An expert hemp farmer 'reads' and understands these ecosystem responses and utilizes the information to maximize crop efficiencies.

Importantly, songbirds and raptors are not the only winged creatures employed by organic hemp and plant nursery growers as part of an organic IPM program.  Chickens, bats and other critters have been successfully integrated into hemp farm pest control programs.  We will discuss these too in future posts.

Finally, it must be understood that birds can be vectors of plant diseases.  However when weighing the risks of potential bird vectored plant diseases versus the insect control benefit, the pest control benefit is usually greater than the disease risk.  

IPM risk benefit analysis can be established through trial and error on the farm, through research of peer reviewed literature and also through coordination with experts working with a local agricultural extension service.

Birds are just one part of a hemp farm ecosystem matrix complex, yet they are a beneficial part.  

Now it is time for me to go add bird food to the feeders!

Organic Hemp Pest Control (IPM) Prescribed and Simulated Burning Importance

 Last post we discussed how Eastern Tent Caterpillars, Malacosoma spp., lay their eggs on the branches, twigs and leaves of hardwood trees.  Once deciduous leaves fall and autumn winds blow twigs to the ground, caterpillar eggs can overwinter in accumulated biomass, groundcover vegetation and the dirt.

Insect, probably caterpillar larve hatched and beginning to weave silken web for protection

Until humans began the suppression of seasonal lightning fires, heat generated by combustion of dry biomass served to control population numbers of many pest organisms including caterpillars.

Natural seasonal fires served to cap population numbers of many pest insects.

Many farming operations today have reintroduced the practice of land fire management with prescribed burning.  Prescribed burning involves the intentional application of fire to plots for the purpose of weed and invasive plant control, pest management, biomass fuel reduction (safety), hunting plantation management and many other purposes.

Often times though, prescribed fire may not be practical for safety sake and sometimes burning is simply impossible, say in a greenhouse for example.  In the event a hemp cultivation area is located in an area where burning is not practical then leaf litter and grounds cleaning becomes a pest management tool of utmost importance.

Pest organisms take advantage of many transportation mechanisms referred to as vectors, to increase, sustain and spread their population numbers.

Leaves and twigs are subject to seasonal winds.  Once deciduous leaves fall from a branch they may be blown hundreds of feet from the tree from which they grew.  Over time these leaves can be carried significant distances via strong breezes.  

Moth laid caterpillar eggs attached to wind blown leaves and twigs can stay viable through winter months and hatch when appropriate weather conditions develop during spring months, increasing hemp pest population numbers.

Leaf litter management will not cause moths or caterpillars to go extinct.  On the contrary, managing tree leaf and twig drop can benefit the moth and caterpillar populations.  Excess caterpillar population numbers and overgrowth may lead to weakened individuals, spread diseases and lead to larval food shortages.  Good leaf management mimics nature's own way of managing insect populations.

As mentioned above, wildfires and lightning fires historically served as a limiting control on caterpillars and other insect egg spread.  As fire frequency diminished, pest pressure increased.  It is not really a big surprise that as the natural complexities of ecology change, a result of human actions, caterpillar and pest overpopulation occurrences are becoming more commonplace.

Today, because of the lack of seasonal wildfires it is important to 'simulate' fire's pest destruction effects by mechanically removing leaves that fall across the hemp cultivation areas.  Importantly, the grower should not only remove tree, leaf and twig litter from active cultivation areas but also from adjacent areas of the cultivation plot or greenhouse area.  Caterpillars and other leaf borne pests can crawl long distances.

Backpack blowers, rakes, lawn mower debris collection bags and other equipment can be employed to collect tree drop biomass (litter).

Once the twigs and leaves are gathered it is necessary to burn, compost or mechanically degrade the biomass to actually destroy pest eggs.  A big pile of leaves in the corner of the property can serve as a giant pest incubator.

Today, understanding and managing the leaf-twig-wind vector complex is just one of many important factors comprising an organic hemp growing ecosystem.

Seasonal fire is always helpful, but not always practical.  Therefore an organic hemp growing IPM program is benefited from simulated fire practices.

Predictable management of pest occurrences is a goal of organic pest IPM.  Keeping leaf litter under control can help keep hemp crops pesticide and toxicity free, and avoid diseases, leaf destruction or bud feces damage.


 Quality, organically grown hemp can bring a high level of demand and offer significant economic gain to the organic grower.  But tent caterpillars can devastate any crop, especially plump, fresh leaves and buds in a matter of hours when they are in a feeding frenzy.  In the eastern U.S. there are several species of tent caterpillars including the Forest Tent Caterpillar, Malacosoma disstria and the Eastern Tent Caterpillar, Malacosoma americanum.  

Eastern Tent Caterpillars crawling across the pavement in search of host plant material

The forest tent caterpillar typically weaves silken mats on tree trunks where they congregate after feeding and for protection.  Similarly, silky tents observed in the branches of trees are usually constructed by the eastern tent caterpillar.

Does Malacosoma americanum pose a serious threat to hemp?  Hemp may not be the first host plant of choice for the eastern tent caterpillar but there are reports in literature (Alexander 1984b) of M. americanum exerting negative pest influence on hemp.  It is possible that once a hungry population of tent caterpillars encounters hemp in cultivation, the caterpillars devour much of a crop without a second thought.  Moreover, in addition to the defoliation, many caterpillars leave copious amounts of feces in hemp's flower buds.

Regardless, this past year brought significant numbers of tent caterpillars to Arendell Hill's trees.  Several of our mature fruit trees were attacked by the caterpillars.  Unfortunately, they ate the majority of buds, blossoms and leaves from many of our citrus and fruit trees. 


It is easy to see just how many tent caterpillars are in a population once they are in their 'tent'.   During their developmental phases, tent caterpillars will crawl out of their nest and feed on the host plant leaves.

Caterpillar eggs can survive the winter attached to leaf litter and fallen tent masses

Worth repeating because of the tremendous potential economic damage a hemp cultivator can suffer is the fact that in addition to tent caterpillars damaging hemp plants by eating their foliage, caterpillars can leave copious amounts of feces as they crawl across and into, eating hemp flower buds.  A feces filled flower bud will usually be considered a total loss.

Eastern Tent Caterpillar's woven 'tent'.

The hemp farmer can avoid significant tent caterpillar damage by taking a few common sense pest management steps including; good housekeeping and a focus on cleanliness, support of biodiversity,  understanding host plant potential and actual pest identification.

First it is important to be able to correctly identify any potential hemp pest caterpillar.  Here in Florida the University of Florida's (UF) agricultural extension program can offer important help to farmers when it comes to growing almost any crop, including hemp.

Most counties in the state have an agricultural agent assigned and if the agent does not personally have the particular pest control experience one needs they will have access to the experts who do.

Here is the link to 'Find Your Local Agricultural Extension Office' website.

Your local agricultural extension agent will be able to assist you in identifying which of the species of tent caterpillars your growing operation may be challenged with.  In addition to the tent caterpillar issue, your UF extension agent can help with any pest issue.hemp 

Along with the agricultural extension services discussed above, the internet is another resource to assist with in pest caterpillar identification.  One hack I always turn to includes snapping a photo with my phone camera and in turn doing a Google image search.  Although not as accurate by any means as the extension expert's identification help, the Google image search usually narrows down pest species choices to family or genus.  Many times however, I've been able to successfully identify caterpillar types through the Google image search function.

Once the caterpillar has been identified, in this case we've identified some of our caterpillars as the Eastern Tent Moth Caterpillar rather than the Forest Tent Caterpillar, then the grower must decide what level of attention needs to be aimed at the potential pest caterpillar.

If the ecological, environmental and economic damage potential is great then the hemp farmer may want to consider an eradication or extra strong management approach.  Eradication often involves pesticide applications, that though they may be considered 'organic' still possess moderate toxicity and lower the value and quality of the final hemp crop.  Additionally, organic pesticides ultimately make a pest problem worse by unbalancing of the farm's long-term, functioning ecosystem dynamics.

If the ecological, environmental and economic damage potential is more moderate but certainly in need of addressing then a focused management approach may be advised.  Moderately focused approaches can be taken many times when pest caterpillars first begin to appear and can include; traps, hand removal, facility cleaning, personal protective equipment, soil and container sterilization and more.

Caterpillar eggs may be attached to fallen leaves and hatch the next warm season.

Finally, if the potential pest is a slow reproducing and easy to control organism them monitoring may be all that is necessary.  Always keep good notes, including dates, times, events, pest numbers and types and control measures taken. 

One of the most common vectors of caterpillar and larvae are fallen leaves

Once the caterpillar has been identified and the level of necessity for adequate response has been decided them control actions can be implemented.

Most importantly, it is crucial to understand the best ecological, environmental and economic outcome will be achieved only when the hemp farmer can bring the growing operation into balance with the surrounding ecosystem that itself is functioning within normal ecological variables.  What this means from a pest control perspective is that any hemp operation will be mostly affected by pests which are themselves existing in an unbalanced state in the soil, vegetation and air in and around the hemp farm.

An eradication effort on the hemp growing area will be effective only as residual pesticide exists.  As soon as the pesticide is degraded additional pests will enter the growing area from the surrounding ecosystem where they are out of balance in excess numbers requiring more pesticides to be applied.  Eradication and pesticide use can easily turn into a repetitive cycle.

However, once the surrounding ecosystem is balanced with respects to ecological dynamics then hemp crop pest control becomes much more manageable.

The hemp farmer must also consider and strive for ecological balance within the totality of their plot, not just their greenhouse or outdoor hemp garden.

As a hemp farmer I can keep tent caterpillars out of my green house on a consistent basis only if the surrounding land is balanced with normal tent caterpillar population dynamics.  If the tent caterpillar populations surrounding the hemp greenhouse are out of balance then eradicating them from the green house will only have momentary benefit for they will crawl right back in once the pesticide level is no longer a deterrent. 

Supporting a natural ecological balance in and around the greenhouse or growing plot the farmer should manage the growing areas in a native and natural manner.  Area native ecosystems have evolved over the millennia into a harmonious complex system of interacting life forms.

Usually nature has fine tuned native ecosystems to function in a precise balance, one where all forms of life play a part and one where all natural geophysical and climatic conditions help maintain homeostasis.

Once humans become involved though we have a tendency to change an ecosystem's natural variables to suite our plans.  Examples of these impacts include; lack of fire, artificial irrigation, replacement of native plant flora with pest prone landscape plants, alteration of natural hydrology, alteration of native soils, change of noise levels, urban heat island effect and much more.

With respect to our tent caterpillars, annual wildfires suppressed for the safety of lives and property, allow a much greater quantity of tent caterpillar eggs to survive in the ground, on bark and on fallen leaves.

Historically, fallen leaves were usually part of the fuel annual lightening fires burned with and much of the egg bank was burned away.  However with a lack of fire today potential pest eggs can exponentially accumulate, creating population numbers that are much higher than in fire acclimated ecosystems.

In the hemp greenhouse and across the hemp cultivation area it is important to keep leaf litter cleaned up.  Leaves left to lie over the winter, especially those in piles under shrubs or around the base of fences make good incubation areas for next years caterpillars.

In the absence of fire, mowing and raking can help control pest eggs.

Leaf litter control is just one of the many integrated pest management control approaches a hemp grower can take.

I try and visualize my growing area as it would have functioned from a biophysical perspective as it might have before humans arrived.

Of the three pest management approaches mentioned above, an IPM approach to hemp cultivation, based on ecosystem principles consistent with balanced, native communities works best for growing quality, organic hemp products. 

We will look at the value of using native plants and avoiding horticultural landscape around the hemp farm, as well wildlife and other IPM tools in upcoming posts.


It is probable that hemp planted green roofs will become a norm in the future.

Hemp is a viable green roof crop with many positive economic and ecological attributes.  For instance hemp is a choice raw material in the making of paper and rope.

But what are the challenges of growing hemp on a rooftop?  There are many.  However, I believe that as in any green roof plant, hemp can be grown across a green roof system with proper consideration given to those challenges.

First, one must be familiar with the hemp plant and its growing requirements.  There are many varieties and cultivars of the hemp plant and each will have its own historically preferred conditions.  So knowing your hemp plant is important.

In addition to understanding hemp's growing requirements you must have a solid knowledge of organic hemp pest control.  I believe all rooftop grown hemp must be treated for pests using only organic integrated pest management (OIPM) principles.

Integrated, organic pest management with an emphasis on cleanliness and exclusion should be the management approach of all green roof operations, hemp or otherwise.  Green roofs are subject to constant winds.  Spraying chemical herbicides and pesticides on a rooftop could potentially expose adjacent neighbors to wind carried toxic compounds.

Irrigation is another issue to be resolved for hemp plants grown on green roofs.  Hemp, as all members of the Cannabaceae, are C3 plants.  C3 plants have evolved photosynthetic systems that are prone to support fast growth but also rapid desiccation potential.  Hemp must not be overwatered yet the plant also requires consistent water supply to its roots.

Before deciding on the best irrigation system for a hemp planted green roof there are other factors to be considered, including; heat tolerance, light levels, flowering requirements and more.  Some of hemp's optimal growing requirements can be addressed with either added mechanical systems or also with plant portability.

Temperatures on a rooftop can reach upwards of 150 degrees F or 66 degrees C.  Hemp won't survive long under those temperatures without a level of temperature mitigation.  Temperature mitigation options can include shade systems such as movable polypropylene screens or planting location strategies which take advantage of existing shade.

Other temperature options can include the possibility of utilizing a portable growing system that can be moved across the rooftop or off the rooftop as necessary.

Of course as with any mechanical system the rule should be; "the simpler the better ".  All mechanical systems can fail.  

Sunlight exposure and shading also have to be factored into flowering requirements.

Green roof winds can also be a serious challenge to fast growing and in some cases tall hemp plants.  Storms can quickly develop and hail or high speed winds may break, damage or topple hemp plants.

Despite all the challenges and considerations a rooftop grower of hemp must take into account, there are potential advantages to green roof hemp cultivation.

Free sunlight, rain, constant breezes and a measurable reduction of vectored pests may be benefits of rooftop hemp farming.

We will look at the many disadvantages and positive aspects of growing hemp on rooftops in future posts.

In the meanwhile, consider the issues associated with growing hemp on a green roof.  Talk with experienced green roof designers and growers.  As hemp becomes more excepted the popularity of hemp green roofs will only increase.


The basic number one rule of effective pest control for hemp cultivation is cleanliness.  Cleanliness in all stages of hemp growing is essential.

A clean hemp cultivation area requires;

1. Floors free of dirt & planting media, debris, trash or litter

2. Sterile planting media

3. Employee education concerning cleanliness practices

4. Shoe sterilization devices at entryways to greenhouses and production rooms

5. Regular trash receptacle maintenance and disposal practices

6. Proper use of disinfection media such as hydrogen peroxide and bleach

7. Education about pest vectors and implementation of immediate pest removal

8. Clean water program

9. Clean growing container program

10. Ongoing Integrated Pest Management (IPM) education and practice implementation

11. more

Clean growing practices is essential for a successful hemp cultivation program.

A good place to start is with the development of a cleanliness mission statement and written practice policy.  We will cover these more in the next few posts.

Bird Feeders & Integrated Pest Management

One easy to do pest control activity is also fun. Installing bird feeders and keeping them well stocked with fresh seed and cleaned on a regular basis is a great way to control pests, get some sunshine and fresh air and manage cognitive health all at the same time (studies show that ongoing interests in birds can support cognitive health). Birds make up an important part of our Arendell Hill Nursery IPM program. 

Bird Feeders Can Be An Important Part of a Hemp IPM Program

We put out fresh seed (wild bird mix and black oil sunflower seeds) daily. The birds are attracted to the feeders situated around the perimeter of a native plant themed pond. On any given day there are so many different types of birds here. Not only do they eat the bird feed but they also devour caterpillars, aphids, bugs and other insects helping keep a desirable ecosystem balance. 

Yes, birds can also be vectors of some pests and diseases but they are also a required component of ecosystem homeostasis. Do you have wild birds as part of your IPM? #IPM #Birds #PestControl #Organic #Sustainability #Agriculture #Hemp

Painted Lady Caterpillar Management

 Almost nothing can do as much damage to hemp plants and flower buds as caterpillars can. 

Painted Lady butterflies are attracted to aster-like wildflowers for use as host plants.

Most larvae go through a number of developmental changes (instars) during their transition from egg into butterfly form.  While in the caterpillar stages these larvae consume as much plant matter as they can and store the foraged protein for future use in egg production as mature butterflies.

There are quite a few caterpillars attracted to and often found on hemp plants.  Today I'd like to briefly talk about the Painted Lady Butterfly, Vanessa spp, butterflies and caterpillars.

Painted Lady caterpillars are often found growing and foraging in hemp leaves and hemp flower buds.  

Painted Lady butterflies will typically lay a single egg on a hemp leaf.  Once the egg hatches and the larvae begins to develop, a thread-like silky mesh will appear wrapped around two or more leaves as the caterpillar builds protective shelter.

Circular chew marks may appear of the edges of leaves as the larvae begin to feed.  In their early stages, the Painted Lady larvae may be light brown colored and spiny.  

During outbreak periods, a large number of Painted Lady caterpillars can significantly damage hemp plants with their voracious plant matter diets.  Not only can the Painted Lady caterpillars eat hemp plant biomass, but they can also (as with any other caterpillar and larvae) leave significant amounts of feces in hemp plant flower buds.  Hemp plant flower buds destined for edible product consumption may be seriously damaged or may even become a total loss.

Painted Lady butterflies and caterpillars serve an important role in our ecosystems however.  Even though they may be considered a pest to hemp cultivation efforts, Painted Lady butterflies should be accepted as a vital component of the ecosystem surrounding hemp cultivation operations.

The key to controlling Painted Lady crop damage lies not in eradication, but in supporting a balanced matrix of insect role within the overall surrounding ecosystem.  Painted Lady butterflies as well as other species are important pollinators for native plants.  Their long proboscis can be more effective at pollination for certain native wildflowers than bees for example.  Native plants are likewise essential for maintaining homeostasis with natural population balances, keeping fungi, bacteria and insects numbers relative to proper balances.

As Painted Lady larvae mature they may develop yellow and black stripes.  One important facet of organic based Integrated Pest Management is an understanding of where pests come from, or pest vector recognition.  Although native insect eradication is not a good idea, and actually a practice that may further aggravate invasive pest problems, it is important to understand where and under what conditions insects thrive.

Painted Lady butterfly host plants include thistles, wild asters and plants in the Boraginaceae and Malvaceae (okra, cotton and mallow) families. 

Large populations of thistle or aster plants may become breeding grounds that create out of balance, excessive population numbers of Painted Lady butterflies.  In natural systems fire among other events control host plant populations thereby keeping insect population numbers in balance.

Within today's agricultural systems many natural events, like fires and deep biodiversity, are suppressed.

Once the hemp grower recognizes host plants for their importance and limiting roles they serve then overall ecosystem and pest balancing is easier to achieve.

Bird feeders around thistle or sunflower patches are one potential approach.  Birds utilize caterpillars as food.  Several bird feeders set up just inside your fence adjacent to a roadside thistle patch can serve to keep Painted Lady butterfly and caterpillar populations from becoming destructive and overwhelming.

Painted Lady caterpillars and butterflies are just one type of many native yet potential destructive 'bugs'.

Learning to recognize the 'bug' and understanding their lifecycles and host plants are all necessary components of an organic IPM program designed to maximize hemp production.  Rather than approach organic IPM from the perspective of 'how do we keep nature out of our hemp populations', we must figure out how to effectively integrate hemp cultivation into a balanced ecosystem in which we live.

Hemp cultivation operations existing 'in-sync' with a balanced surrounding ecosystem will be highly productive and efficient.  Organic IPM programs can be one of the hemp farmer's best grow partners.

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