Alkaloids in the terminal capsule of M–89 variety of P. somniferum rise and plateau as the plant matures in a controlled environment. Lancing immature capsules does not increase yield of codeine plus morphine in the above-ground plant, but lancing may translocate alkaloids upward to the capsule. Poppies produced a high proportion of codeine relative to morphine. This effect is probably due to some environmental condition imposed.