422 MINNESOTA STATE HORTICULTURAL SOCIETY. 



Mr. Elliot: Not less than four feet apart, and I do not know but 

 6x8 feet would be better. 



Mr. Richardson: I have had thirty years experience in planting 

 windbreaks, and I have noticed just this, that those who planted 

 their groves thick have got small miserable trees, and there are no 

 trees down our way that amount to anything except those that have 

 plenty of room. 



Mr. Clarence Wedge: I want to say a word in regard to what Mr. 

 Richardson has said. I have seen groves west of us in the central 

 portion of the state that were planted four feet apart each way 

 They were not planted with cottonwood, but with good ash and elm 

 and they were a perfect 8ucces.««. 



Mr. Richardson: How tall were they? 



Mr. Wedge: As tall as this room. (About 14 feet). 



Mr. Richardson: They will have to put the axe to them. 



Mr. Wedge: Of course, that is the expectation. 



RELATION OF BIRDS TO HORTICULTURE. 



PROF. OTTO LUGGER, MINN. STATE EXPERIMENT STATION. 



When we read books that treat of birds, we usually see it stated 

 that some are insectivorous while others are granivorous. The 

 former are claimed to be decidedly beneficial, while the latter 

 are considered more or less injurious. These statements 

 have been made by ornithologists who have studied most 

 carefully the structure and life history of their pets, and, con- 

 sequently, their verdict ought to have some weight. If, how- 

 ever, the botanists and entomologists are consulted, or scientists 

 who have studied the relation of insects to plants or the relation of 

 plants to man, we soon discover that doctors disagree and that the 

 claimed superiority of insectivorous birds over others is far from 

 being true. The only and true way of studying the value of insecti- 

 vorous birds as destroyers of insects is with the aid of the knife; in 

 other words, we have to study the contents of the crop and stomach 

 of a bird, separate out the different insects and seeds, hand them 

 over to the entoiuologist and botanist and let them decide the ques- 

 tion of their relation to horticulturists and farmers. It will then be 

 found that some birds which eat nothing but insects may be injuri- 

 ous to our interests, while birds feeding upon seeds may be decid- 

 edly beneficial, it all depending upon the character of the food 

 consumed. 



Let us make a rough estimate of the insects found in the United 

 States. Supposing we have 50,000 different kinds of insects, we 

 know frotn sad experience that among these insects are a nuinberof 

 very destructive ones, but even if we count the less injurious ones 

 we have all told not more than 500 really injurious kinds of insects 

 in the United States. This means that out of every hundred insects 

 consumed by birds only one is an injurious one. Of course, this 

 proportion is true only when birds are uniformly distributed over 

 the country, as they usually are during the summer, and not con- 

 gregated together in vast numbers, as they may be if food is 



