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Psyche 
[Vol. 88 
wooded areas and cultivated fields. The soils were well-drained and 
flower bloom was profuse. More than 150 entomophilous species 
bloomed on the field. The most common woody plants were red 
maple (Acer rubrum), staghorn sumac (Rhus typhina ), and various 
willows (Salix spp.), dogwoods (Cornus spp.), and brambles (Rubus 
spp.). The dominant herbaceous plants included several entomo- 
philous species and the grasses timothy (Phleum pratense) and 
orchard grass (Dactylis glomerata). 
I sampled Apoidea by walking transects and capturing bees from 
flowers. There were 10, 30 m transects randomly-placed on the field. 
I took transect samples during times of maximum foraging activity 
(1000-1600 hours) throughout the season (at least 3 samples in each 
2-week period, late May-October, 1974 and 1975). I used all-day 
samples from randomly-selected patches of common flower species 
(throughout the growing season, 1975 and 1976) to confirm the 
results from the transect samples and to study spatial distributions 
of foraging bees. Voucher specimens of the bee species are placed in 
the Cornell University Insect Collection, lot number 1039. 
I counted the number of flowers of each species at anthesis in 100, 
lm 2 subquadrats. The subquadrats were arranged in groups of 10, 
randomly-placed within 30 m X 30 m quadrats (the bee transects 
were also within these quadrats). There were 10 quadrats randomly- 
placed on the field. Flowers were sampled once every 2 weeks 
throughout the season. Voucher specimens of the plant species are 
placed in the Bailey Hortorium Herbarium, Cornell University. 
Details of the field techniques are given by Ginsberg (1979). 
I used the records of Fernald (1950) and Wiegand and Eames 
(1925) to determine whether flower species were native or were 
introduced into the area. Their determinations were based largely 
on the records of early botanical explorers (e.g. Pursh 1923) and on 
previous species lists for the area (e.g. Dudley 1886). Admittedly, 
there is some margin for error in these judgements, but because of 
the large number of entomophilous species on the sample site, 
mistakes about the points of origin of a few species should not 
influence the major arguments. 
Results 
Red maple was the first abundant flower species to bloom on the 
field in spring. Several willows and rosaceous trees (Prunus cerasus, 
