162 College of Forestry 
be the case where a mixture of clay and sand and fine gravel 
made up the deposit lying as some of our valley soils do. 
Our richest farming regions have been developed upon such 
soils. Naturally the demand for soils of this favorable 
moisture relation for farming purposes means that not many 
exist which are not either intensively cultivated or covered 
with climax forest (the carefully preserved woodlots) and 
hence few situations are offered where the natural mesophy- 
tic sequence is observable from the beginning. If we take 
the common ease of an abandoned field there is always asso- 
ciated therewith a condition of aridity which determines a 
tendency toward xerophytic succession. Thus the hill farms 
of southern New York with their cover of moss (Polytrichum 
mats), sparse grasses, daisies, golden rod, field cats-foot (An- 
tennaria neglecta Greene) hawk weed, etc. ; of sweet fern and 
sometimes of blueberries; of shrubs of white birch, aspen, fire 
cherry, sumac, etc.; and finally of seedlings of pine, maple, 
ete., show a relationship to the xerophytic successions (as 
I have here defined them) upon sand and burns (as in the 
Catskills and Adirondacks). 
An abandoned stony field in central New York has been 
under my observation for some twenty years during which 
period essentially the following progress has been made 
toward mesophytic (climax) forest ; (1) dominance of field 
weeds; (2) of sparse grasses — timothy, blue grass and pas- 
ture weeds, orange bos eres ox-eye daisy, 2 olden TOO s(Co)) 
invasion by red raspberry and blackberry, the latter becom- 
ing dominant (a much sought blackberry “ patch”); (4) 
invasion of the blackberry stage by sumac; (5) gradual ap- 
pearance of fire cherry and species from surrounding swamp 
and climax forest (white pine, elm, yellow birch, ash, bass- 
wood, red maple, hemlock, ete.); (6) shading of ground, 
elimination of shrubs, ete., first by the most vigorous invader, 
white pine, and later by broad-leaved trees. In some part of 
the field the forest crown is forming and thus the “old field ” 
stage is passing. During all this period the forest forming 
element has been hindered by berry pickers who have habitu- 
