The opium poppy is botanically classified as Papaver somniferum. Of all these species, only P. somniferum and P. bracteatum produce opium in any significant amount, although the latter is not used at present as a commercial drug source but is sometimes grown as decorative blossom. Papaver somniferum is an annual with a growth cycle of approximately 120 days. It requires a rich, well-cultivated soil and, in the wild, is more likely to flourish in recently dug or ploughed ground, hence its presence in farm fields.
The flower is short-lived. In two to four days the petals drop, exposing a small, round pod the size of a large pea. In its raw state, opium is the dried latex or juice of the seed pod which is also known as the capsule, bulb or poppy-head. It is an opaque, milky sap which, although found throughout the plant, concentrates the active ingredients in the pod. Harvesting opium is obtained by tapping the individual pods. The harvest begins about two weeks after the petals have dropped. Today, the tapping tool is generally a specialized knife consisting of a set of three or four parallel steel or glass blades mounted on a handle. This is run vertically over two or three sides of the pod. If the blades cut too deeply into the pod wall, the opium will flow too quickly and drip to the earth where it will be lost. The tapping (also known as scoring or lancing) is sometimes carried out in the late afternoon in the hope that the opium will ooze out overnight and coagulate slowly on the surface of the pod.When the opium first appears, it is a cloudy, white, fairly mobile substance but on contact with air it oxidizes, turning into a dark brown, viscous substance, sticky to the touch with a distinctive delicate perfume. The opium, now a resinous gum, is carefully scraped from the pod with a short-handled blade. In order to prevent the blade from becoming covered in gum, the farmer wets it between plants.
A pod will continue to secrete opium for some days and may be tapped up to half a dozen times. The opium yield varies according to the size of the pod and the efficiency of the farmer. The average is 50 milligrams per pod, a hectare of poppies providing, between 8 and 15 kilograms of raw opium.
|Opium poppy - LINK|
|Scoring the pod to milk the opiates - LINK|
|Scoring the pod to allow the sap to ooze out. Photo credit: Colin Summers|
|Photo credit farmer dodds on Flickr|
|Scored pod oozing opium - LINK|
|Turkish poppy oozes sap that will later be harvested. Photo credit: Gamma/Liaison - LINK|
|Sap being left to harden before being collected by a farmer - LINK|
|A farmer scrapes off raw opium that has oozed out of the pod - LINK|
|A latex containing several important alkaloids is obtained from immature opium poppy seed capsules one to three weeks after flowering - LINK|
|Collecting the hardened sap from the pods - LINK|
|Raw opium - LINK|
|An opium farmer collecting raw opium. Photo credit: Aaron Huey|
Info from here