96 MICHIGAN ACADEMY OF SCIENCE. 



He has learned to see that the visits of insects to the flowers aid in 

 ensuring a larger crop of fruit, as he knows that the showy portions of 

 the flowers are hung out as mere adAertisenients, to attract insects; that 

 surplus pollen and nectar are placed in the flowers as wages to reward 

 and encourage their visits. 



Some knowledge of botany, at least, is essential to aid the judgment 

 in selecting with intelligence the sorts that may be crossed or hybridized. 



Long ago, Darwin learned that some pistils refused to be fertilized 

 by pollen upon the same individual plant, that pistils of a horticultural 

 variety were not well fertilized by flowers of the same variety. 



Some years ago, a man in Virginia owned an orchard consisting largely 

 of Bartlett i^ears, in which were scattered other varieties. The Bart- 

 letts were so prolific and profitable that a near neighbor set 22,0(J(» 

 standard Bartletts in a block, which, with good care for eighteen years 

 had never borne over one-fourth of a crop. The trees had been well 

 cared for. In 1894, M. B. ^N'aite of the United States Department of 

 Agriculture, published a bulletin giving the results of his' investiga- 

 tions of these orchards and learned the reasons for the eminent suc- 

 cess of one orchard and the lack of success of the other. Here are some 

 of his conclusions: 



I. Many of the common varieties of pears require cross-pollination, 

 being partially or wholly incapable of setting fruit when limited to 

 their own pollen. 



3. Cross-pollination is not accomplished by applying pollen from 

 another tree of the same grafted variety, but is secured by using pollen 

 from a tree of a distinct horticulture variety, i. e., which has grown 

 from a distinct seed. Pollen from another tree of the same variety, is no 

 better than from the same tree. 



4. The impotency of the pollen is not due to any deficiency of its 

 own, but to the lack of affinity between the pollen and the ovules of the 

 same variety. 



5. The pollen of two varieties may be absolutely self-sterile and at 

 the same time perfectly cross-fertile. 



7. Bees and other insects are the agents for the transportation of 

 pollen. 



II. Self fecundated pears are deficient in seeds, usually having only 

 abortive seeds, while the crosses are well supplied with sound seeds. 



From these experiments he arrived at the following practical direc- 

 tions fop growing pears: 



1. Plant mixed orchards, and not solid blocks of one variety. 

 3. Be sure that there are suflicient bees in the neighborhood or with- 

 in two or three miles to properly visit the blossoms. 



Mr. Waite and others have shown that the same rules apply to or- 

 chards of apples and plums. 



Botany is often a great help to a man in detecting a new weed, while 

 it has yet only been sparingly introduced. If then attacked, it may be 

 easily subdued, before spreading all over the farm. The unbotanical 

 person might scatter quick grass and other troublesome pests far and 

 wide over his premises before he became aware of their presence. A 



