Below are the Introduction and Conclusion to an experiment performed in order to explore how cannabinoids (such as THC) are arranged on the surface of a cannabis leaf. Interestingly, the authors conclude that cannabinoids are actually found in structures other than the glandular trichomes.

In other words, even if a nugget isn't totally covered in crystals, it still has the potential to get you mega-stoned......this is just scientific evidence of this fact!!!

Link to actual article:
http://www.unodc.org/unodc/bulletin/...1_page007.html



Cannabinoid composition and gland distribution in clone of Cannabis sativa L. (Cannabaceae) *
Jocelyn C. TURNER,
John K. HEMPHILL
Paul G. MAHLBERG
Department of Biology, Indiana University, Bloomington, Indiana 47401
Introudction

Gladnular trichomes covering the plant surface have been implicated as the source at cannabinoids in Cannabis sativa L. (DePasquale, 1974: Malingre et al., 1975). Harmmond and Mahlberg (1973,1977), in their scanning electron microscope study of these trichomes, described three gland types: the bulbous gland which consists of a large multi-cellular head, and the capitate-stalked gland which consists of a large multi-cellular head, that terminates a stalk of variable height. Non-glandular trichomes are also present in abundance on the plant epiderrmis (Ledbetter and Krikorian, 1975). Fairbairn (1972) reported the presence of cannabionds in both capitate-sessile and capitate-stalked glands and indicated that capitate-stalked glands were the major cannabinoid containing glands. DePasquale (1974), in an ultrastructural-study of be a capitate-stalked glands, interpreted the secretory part of the gland to be combination of the gland head and perhaps apical stalk cells. Malingre et al. (1975) concluded that cannabinoids were present mainly in the epidermal glands and not in mesophyll cells or non-glandular trichomes, although there was some indication of cannabinoid content in the least mid-rib.

The purpose of this investigation is to determine whether a correlation exists between glandular trichomes and cannabinoid content in cannabis. If specific glands are associated with cannabinoid content, a correlation should exist between the gland number present on a particular plant and the cannabinoid content of that part. Futhermore, it should also be possible to establish a correlation between the number of each gland type and cannabinoid content.


Conclusions

The relationship between glandular trichomes and cannabinoid content in Cannabis sativa L. was investigated. Three strains of cannabis, which are annuals, were selected for either a drug, a non-drug, or a fibre trait and then cloned to provide genetically uniform material for analyses over several years. The distribution of the number and type of glands was determined for several organs of different ages including the bract, and its subtending monoleaflet leaf, and the compound leaf on pistillate plants. Quantitation of glands on these structures was integrated with gas chromatography analyses to determine their cannabinoid content. A negative correlation was found between cannabinoid content and gland number for each of the three clones. Isolated heads of the capitate-stalked glands also were analysed for cannabinoid content and found to vary in relation to clone and gland age. These studies indicate that cannabinoids may occur in plant cells other than glandular trichomes. The results of these studies emphasize the need for stringent sampling procedures in micromorphological studies on trichome distribution and analytical determinations of cannabinoid content in cannabis.