A Comparative Study of the Number and Length of Roots Produced in Nineteen Angiosperm Species

Abstract

Quantitative studies of the roots of 19 spp. of plants in 14 angiosperm families were made with the results presented in tabular form. Tertiary roots produced about one quaternary root per cm. of length in most of the plants examined; however, the number of secondary and tertiary roots developing from main and secondaries, respectively, varied considerably. Variation in number of roots and root length results from differences in size of plant, age, inheritable stability, and competition with other plants. Generally, plants show a compensating factor in root growth; when restricted in one category, another root division or two will exhibit much greater growth.