Longevity of Weed Seeds

Manawatu Times, Volume LIV, Issue 6620, 5 August 1931, Page 9

Longevity of Weed Seeds

REMAIN ALIVE FOR DECADES Like tho Indians who covered their bodies* with oil - for protection,', nature has given to some seeds an oily coating, for the same express purpose. ‘ Oily seeds and hard, thickcoatcd seeds usually live the longest; Seed coat, heredity and environment all play important roles in the life of seeds in general. Through countless years of natural selection only tho hardiest weeds and weed seeds have survived to this day; it is the law of tho survival of the fittest. Many weeds have inherited from their ancestors tho ability to remain dormant and alive in the soil for decades. Seeds from cultivated plants are not the same; they die at an early age in the soil, but survivo many years under the ideal conditions which are found in a dry granary. When dry and ripe, seeds will stand an almost unlimited amount of frost. If wo want to destroy weed seeds we must give them harsh treatment. Heat and moisture are their worst enemies, and a few weeks in a heating manure pile snuffs out their little lives. Life of Cereals and Other Seeds

Exhaustive experiments on tho life of •wheat, oats, barley and other seeds have been conducted by the seed branch of tho Department of Agriculture at Ottawa, in the United States, in England and in Denmark. Wheat and barley retain their vitality almost unimpaired for five years after harvest. Oats show little loss of vitality until after the ninth year. This refers to grain sufficiently ripe when threshed not to heat in storage and when stored in perfectly dry warehouses. The germ of all the wheat was practically doad.at the end of the 15th. year, but after the same length of time oats still gave a fairly high germination, The longer, life of oats as contrasted with wheat is probably due to the protection of the oat hull.

Tho vitality of timothy seed in dry storage was well maintained until after the fourth year, while alfalfa)’red clover, alsiko and white clover showed little reduction in germinating . power during the first three years after harvest. Swede turnip seed retained good vitality for four years. The results of those experiments point to the possibility of holding, when desired, seed grain, clover and grass seed over a period of three or four years without seriously reducing its percentage of germination. It is customary, however, and usually desirable to sow fresh, clean seed every year.