308 Gardening 
OE: 
Univ. of Wis. Agric. Expt. Sta. 
Fic. 173. The rows of cabbage at the right were grown from seed from re- 
sistant stock. They have inherited the power of the parent plants to resist the 
disease. The plants on the left are from ordinary seed. 
conducted by agricultural experiment stations or by seed 
firms that produce seeds on a large scale. However, the 
home gardener may secure seed, whenever available, of 
desirable varieties known to be resistant to certain 
diseases. When a disease tends to reappear year after 
year, resistant varieties are especially valuable. For 
example, the fungus that causes the’ yellows ” of cab- 
bage is believed to persist in infected soil for a number 
of years, and the growing of cabbages in such soil is only 
possible when one uses seed of plants that are resistant 
to this disease (see Figs. 172 and 173). 
Whenever any noticeable and markedly injurious fun- 
gous disease or insect (see next chapter) appears among 
any of the vegetable crops, one should determine with- 
out delay the nature of the injury. If this cannot be 
