Variations by Plant Part
The concentration of cannabinoids depends on the plant part, or more specifically, the concentration and development of resin glands to plant part. The female flower bracts have the highest concentration of resin glands and are usually the most potent plant parts. Seeds and roots have no resin glands. These shoe no more than traces of cannabinoids. Smoke seeds will give you a headache before you can get high. If you got high on seeds, then there were probably enough bracts adhering to the seeds to get you high.
Here are the potencies, in descending order, of the various plant parts:
1. Female flowering clusters. In practice you don't separate hundreds
of tiny bracts to make a joint. The whole flowering mass (seeds removed),
along with small accompanying leaves, forms the material.
2. Male flower clusters. These vary more in relative potency depending on
the strain (see "Potency by Sex," below).
3. Growing shoots. Before the plants flower, the vegetative shoots (tips)
of the main stem and branches are the most potent plant parts.
4. Leaves (a) that accompany flowers (small);
(b) along branches (medium);
(c) along main stem (large).
Generally, the smaller the leaf is, the more potent it can be.
5. Petioles (leaf stalks). Same order as leaves.
6. Stems. Same order as leaves. The smaller the stem (twig), the
higher the possible concentration of cannabinoids. Stems over 1/16"
in diameter contain only traces of cannabinoids and are not worth
smoking. The small stems that bear the flowers can be quite potent.
7. Seeds and Roots. Contain only traces (less then .01 percent) and
are not worth smoking or extracting.
This order is fairly consistent. The exceptions can be the small leaves that accompany male flowers, which are sometimes more potent than the flowers themselves. The growing shoots are sometimes more potent than the mature female flowers.
Samples of pollen show varying amounts of cannabinoids. Resin glands are found inside the anthers, alongside the developing pollen grains, and form two rows on opposite sides of each anther. Pollen grains are smaller than the heads of large resin glands ({see Plate 7}), and range from 21 to 69 micrometers in diameter21. A small amount of resin contaminates the pollen when glands rupture, but most of the THC in pollen samples comes from gland heads that fall with pollen when the flowers are shaken to collect it. One study, using pollen for the sample, found concentrations of up to 0.96 percent THC, more then enough to get you high79.
