Yield of Illicit Indoor Cannabis Cultivation in The Netherlands

Abstract

To obtain a reliable estimation on the yield of illicit indoor cannabis cultivation in The Netherlands, cannabis plants confiscated by the police were used to determine the yield of dried female flower buds. The developmental stage of flower buds of the seized plants was described on a scale from 1 to 10 where the value of 10 indicates a fully developed flower bud ready for harvesting. Using eight additional characteristics describing the grow room and cultivation parameters, regression analysis with subset selection was carried out to develop two models for the yield of indoor cannabis cultivation. The median Dutch illicit grow room consists of 259 cannabis plants, has a plant density of 15 plants/m(2), and 510 W of growth lamps per m(2). For the median Dutch grow room, the predicted yield of female flower buds at the harvestable developmental stage (stage 10) was 33.7 g/plant or 505 g/m(2).

Yield and turnover of illicit indoor cannabis (Cannabis spp.) plantations in Belgium

“…Since upon discovery, police has usually little clues on the precise nature of varieties used by growers, Toonen et al [5] could not account for variability in yield between different so-called cannabis strains. Vanhove et al [7] showed that the variety used is a main yield-determining factor in indoor cannabis production.…”

“…The study results of Toonen et al [5] were based on discovery and confiscation of 77 indoor cannabis plantations for which yield was estimated at the spot. Since upon discovery, police has usually little clues on the precise nature of varieties used by growers, Toonen et al [5] could not account for variability in yield between different so-called cannabis strains.…”

“…Due to the current lack of hard facts, Belgian judiciary is forced to make rough estimations of the profits gained, based on estimates of crop yield of seized cannabis plantations and wholesaler prices used in -amongst others -Dutch coffeeshops. Today, the Belgian judiciary uses a crop yield estimation made by the University of Wageningen, The Netherlands [5] and set at 28.1 g of dry female flower buds per plant (lower bound of the one-sided 95% confidence interval). For subsequent estimation of financial profits, the Belgian police currently relies on data obtained from internet sites, the Dutch police and Belgian judicial files.…”

Cannabis cultivation in Quebec: Between space–time hotspots and coldspots

“…The instability of clusters in a region might follow the effectiveness of a police intervention or indicate resilience if a hotspot returns. In addition, spatial and temporal analysis are relevant for other jurisdictions that, like Quebec, have domestic producers of cannabis: other provinces of Canada (Ontario Association of Chiefs of Police, 2003), the United States (Hurley, West, & Ehleringer, 2010;Weisheit, 2011), the United Kingdom (Potter, 2006), New Zealand (Cocklin et al, 1999) and the Netherlands (Toonen, Ribot, & Thissen, 2006).…”

Trend of the psychoactive potential of Cannabis sativa l: Plant samples

“…This plant can be grown on every continent and almost in every country, whereas indoor growing, which has recently become more popular, also contributes to its expansion. In the last decades, there has been an increase of indoor growing of cannabis plant in many countries, which, apart from resulting in the greater yield, also has a significant effect on the chemical composition of the plant (TOONEN et al, 2006). The main psychoactive component of C. sativa is 7, 8, 9, 10-tetrahydro-6, 6, 9-trimethyl-3-pentyl-6H-dibenzo (b, d) pyran-1-ol, also known in forensic literature as (-)-trans-Δ 9 tetrahydrocannabinol, or simply tetrahydrocannabinol (THC) (BRENNEISEN, 2007).…”