Physiology and botany of industrial hemp.

Abstract

This chapter presents the hemp's anatomy and morphology, together with its chemical composition and properties. It also details the particularities and specificities of the plant's vegetative cycle, which is consists of emergence, implantation (3 weeks after emerging from the ground), active growth, flowering, full flowering and end of flowering. Calculation of potential hurd yield of a hemp crop is briefly explained.

Potential of hemp (Cannabis sativa L.) for paired phytoremediation and bioenergy production

“…The growth and reproductive cycle progression of hemp is photoperiod-sensitive. Hemp plants can grow to heights of up to 5 m and can develop a tap root penetrating up to 2 m into the soil (Chabbert et al, 2013;Clarke & Watson, 2007;Ehrensing, 1998). The majority of aboveground hemp biomass comes from the tall lignocellulosic plant stalk (Trey et al, 2019), which has been used for fiber for thousands of years (Li, 1973).…”

Performance of Different-Use Type Industrial Hemp Cultivars under Mid-Atlantic Region Conditions

“…The critical day length is longer for male plants than for female plants of the same cultivar [20]. Because flowering depends on cumulative degree days since planting and cultivar's photoperiodic behavior and sensitivity, differences in cultivar sensitivity to light could impact crop yield [21]. Planting too early in spring results in low and poor germination and emergence while late sowing reduces the plant growth period and quality and quantity of yields [17].…”

“…Planting too early in spring results in low and poor germination and emergence while late sowing reduces the plant growth period and quality and quantity of yields [17]. After the implantation phase, and when active growth starts, the temperature sum accumulation starts to influence yield [21] and depending on intended use, crop harvest timing can impact yield and quality of hemp products. For fiber, harvest should be carried out during male flowering or during the flowering for monoecious crops.…”

Hemp and flaxseed oil

“…The botanical classification of hemp is still a controversial topic (Allegret, 2013;Chabbert et al, 2013). This chapter will focus on Cannabis sativa L. Hemp is one of the first cultivated crops, dating back 4000-6000 years ago.…”