Organic Hemp Variety Trials
Industrial hemp (Cannabis sativa) is a
fiber, oil and seed crop with a 5,000 year
history of cultivation. It was first
planted in Kentucky in 1775, and Kentucky's Bluegrass
region was the center of the US hemp industry through much of
Kentucky's hemp industry declined
rapidly in the late 1800s, recovered briefly during the
two world wars, and virtually disappeared by the late 1940s.
Contributing factors to the decline included competition from
cheaper imported fibers like jute, manila, and sisal; falling
costs of domestic cotton production; and increased regulation.
Hemp production was restricted by the federal Marihuana Tax Act of 1937, which required hemp growers, importers, and processors to be registered and taxed. The Controlled Substance Act of 1970 made hemp a controlled substance under Federal Law, with production regulated by the US Drug Enforcement Administration (DEA).
Kentucky is one of several states to have legalized
the cultivation and research of industrial hemp. The 2014 Farm
State Agriculture Departments, colleges and universities to
grow hemp for academic or agricultural research purposes in
states such as Kentucky, where industrial hemp farming is
legal under state law.
Although few Kentucky growers have experience with industrial
hemp, it is widely grown in more than 30 other countries,
including Canada, which supplies many of the hemp products
sold in the USA. Canadian hemp growers have been able to
obtain premium prices for certified organic seed: In 2003-04,
conventional hemp seed sold for 50-60 cents per pound, while
organic seed fetched 85
cents per pound. By 2012, conventional hemp seed prices
had increased to 70-80 cents per pound, while organic sold for
Hemp is reputed to out-compete many weeds, which could make it a valuable component of organic crop rotations in Kentucky. A particular concern to Kentucky's organic growers is the perennial johnsongrass (Sorghum halepense), which spreads rapidly by seed and rhizome, diminishing yields of many crops. Hemp's tall canopy, deep roots, and dense, thick growth habit may enable it to smother johnsongrass when used as a component of organic rotations. According to The Western Agriculturist and Practical Farmer's Guide (1830), "Nothing cleanses and prepares the earth better for other crops (especially for small grains or grasses) than hemp. It eradicates all weeds and when it is taken off, leave the field not only clean, but smooth and even."
Kentucky State University is conducting hemp variety trials
on certified organic land in 2014, to determine yield and
competitiveness of hemp varieties that show promise for
certified organic production on small farms in Kentucky.
- Compare yield and quality parameters of four hemp varieties grown on certified organic land.
- Evaluate hemp's ability to compete with johnsongrass (Sorghum
Variety Trial. The organic hemp variety trial will be
conducted in 4' x 16' plots containing six rows each (8" row
spacing). Sixteen plots will be divided into four randomized
complete blocks, each containing four hemp varieties: (1)
Finola FIN314; (2) Fedora cross; (3) Kompolti; or (4) a
Kentucky heritage variety. Seed will be drilled into prepared
soil in April. Aboveground biomass will be collected from
subplots 50, 75, 100, and 125 days after planting, then dried
to measure dry matter production. Seed will be collected and
weighed at final harvest, and oil will be extracted and
Weed Competition Trial. In April, 2014, an area
infested with johnsongrass (S. halepense) will be
cultivated and divided into twenty 4'-wide strips, arranged in
a randomized complete block design. Each block will be seeded
to one of four crops thought to have potential for
johnsongrass mitigation in organic crop rotations: (1)
buckwheat (Fagopyrum esculentum); (2) kenaf (Hibiscus
cannabinus); (3) cowpea (Vigna unguiculata) and
hemp (C. sativa). A fifth strip in each block will be
left uncultivated, and mowed periodically to prevent
johnsongrass seed set. Aboveground biomass will be collected
from subplots 50, 75, 100, and 125 days after planting.
Biomass will be divided into cover crop, johnsongrass, and
other weed components. Each component will be dried to measure
dry matter production. The demonstration will be repeated in
2015, with half of each plot planted to the same cover crop as
in 2014, and the other half planted to corn.
- Mike Lewis for providing hemp seed.
- Mac Stone, Kirk Pomper, and Teferi Tsegaye for administrative support.
- Kentucky Department of Agriculture, for arranging
university hemp trials.