516 Phylum Arthropoda 



Families sphecidae, andrenidae, and 



MEGACHILIDAE 



METHODS FOR REARING WILD BEES, WASPS, AND 



THEIR PARASITES 



Charles H. Hicks, University of Colorado 



THE writer has successfully reared a large number of bees, wasps, 

 their parasites, and other insects, during the past ten years. Insects 

 from ground nests, as well as those from exposed nests attached to stones 

 or other objects, or those found in stems and in hard wood (such as in 

 logs, stumps, sawed blocks, and the like) have, with few exceptions, 

 yielded a total and maximum number of the possible and expected 

 adults. The following is an abbreviated account of the methods used 

 and of the results attained. 



It is not the purpose to point out here the detailed methods of locat- 

 ing insect nests except to indicate a few general and fruitful sources. 

 Probably the easiest one involves the finding of nests of bees and wasps 

 in wood. These may be obtained during any month of the year in 

 almost any region from old stems or from pith-bearing plants. Espe- 

 cially favorable for nest sites are the stems of sumac, blackberry, rasp- 

 berry, rose, elder, mullein and various weed stems. These are usually 

 stems which have been cut off in one way or another or which have 

 been broken by wind or other agent leaving the pith exposed and easily 

 accessible to the insects. The stems containing possible nests have visible 

 openings or tunnels in the exposed end. If plugged flush across this end 

 or slightly below it, the characteristic plug or outer barricade reveals 

 the builder. The cap may be of resin and pebbles, cotton, mud or other 

 materials, depending on the species building it. Usually, the cancavity 

 in the pith reveals the presence of a nest beneath or beyond. When 

 a stem is suspected of containing insects, it may be split open with a 

 jackknife and further investigated. The old or empty ones may be 

 discarded ; the others brought to the laboratory for further study. 



It has been found that test tubes of sizes varying to meet the specific 

 measurements of particular stems, may be used as containers and the 

 insects reared or the adults obtained. A plug of cotton, packed suffi- 

 ciently tight to prevent the insects from working their way out, prevents 

 escape even of the smallest forms and at the same time allows for ex- 

 changes of gases in respiration. 



My plan has been to give each tube containing a nest, a number which 

 corresponds to the like number on a filing card. This card holds 

 pertinent data. The practice has been to stick a label with a number 

 on the outside of the tube and to place the same number on a loose 



