SEED DISTRIBUTION 171 
Fruits, clusters of fruits, and plants full of fruits are rolled 
along the ground (especially over the snow) by the wind, 
often for great distances, scattering seeds as they go. If it isa 
whole plant that travels, or a large part of a plant, it is known 
as a tumbleweed. Such are the Russian thistle (Salsole), 
tumble-mustard GSisyindrium), winged pigweed (Cycloloma), 
ghost-plant (Amaranthus), and the fruit cluster of old-witch 
grass (Panicum); the white-pine 
cone is an example of a single fruit 
traveling in the same way. 
Many aquatic plants, as grasses, 
rushes, sedges, water dock, lotus, 
bur reed, and a multitude of other 
species, have fruits or seeds which 
float, often for long distances, and 
then lodge and grow. 
Burs of many kinds (fig. 150) 
lodge in the hair, fur, or feathers of 
passing animals and are finally dis- 
lodged in various distant places 
where they may grow. 
163. Dispersal of edible seeds. 
Edible seeds and fruits (such as 
nuts, the grains, and berries) and 
stone fruits (like plums and cherries) are frequently swal- 
lowed by animals and later voided undigested and in a con- 
dition to grow. In this way wild cherries (fig. 151) and wild 
apples are planted about pastures and in open woods. Also, 
raspberry, currant, and gooseberry bushes, asparagus, and 
bittersweet may be found growing in the forks of trees 
(fig. 152). Squirrels, blue jays, and some other animals carry 
away nuts and bury them, often leaving them to grow the 
following spring. 
+, 152. Red rasp- 
berry bush in fork 
of a maple 
10On the general subject of seed dispersal see Kerner-Oliver, Natural 
History of Plants, pp. 833-877, Henry Holt and Company, New York; 
also Beal, Seed Dispersal, Ginn and Company, Boston. 
