. Bulletin (Pennsylvania Department of Forestry), no. 11. Forests and forestry. n ovary, form what is termed the fruit. The fruit may in addition comprise modifications of other organs intimately connected with the ovary. Seeds are productive of the flower and are usually regarded as reproductive organs, but in reality they are the result of reproduc- tion. Their chief work is the dissemination and the protection of the offspring of reproduction. They are usually covered by hard and impermeable coats which protect the young plant contained within from the many dangers with which it is beset. N
. Bulletin (Pennsylvania Department of Forestry), no. 11. Forests and forestry. n ovary, form what is termed the fruit. The fruit may in addition comprise modifications of other organs intimately connected with the ovary. Seeds are productive of the flower and are usually regarded as reproductive organs, but in reality they are the result of reproduc- tion. Their chief work is the dissemination and the protection of the offspring of reproduction. They are usually covered by hard and impermeable coats which protect the young plant contained within from the many dangers with which it is beset. Nature tries to guard against these dangers by developing suitable protective cover- ings for each species. Nature, however, is not always satisfied by simply developing a thick and impermeable coat, but in addition it develops an internal tissue which is compact and contains little water. If a seed possess these essentials it is well protected against most of the destructive agencies to which it is exposed. The chief dangers to which seeds are subject are premature germination, loss of vitality, and destruction by animals. Each seed usually has a suitable covering which regulates the germination in spring. This regulation is necessary so as not to allow the tender plant to emerge before the external growth conditions are favorable for its develop- ment. An embryo within a thin-coated seed would often be stimu- lated by a few warm days in spring with the consequence that the resulting tender plants would be killed by later frost. Nature acts as a guardian and places a thick coat around such embryos, and as a result they are not stimulated until later when frost danger is past. Food is stored in various plant organs such as roots, stem, and branches, and is usually most abundant and conspicuous in the seeds. It occurs in various forms and may often differ in composi- tion. Food stored in the seed is very valuable because it supplies nourishment to the small and tender plants befo
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