244 BOTANICAL GAZETTE [MARCH 
are a fire menace, (3) burning the slash broadcast the first spring or fall after 
logging, and (4) keeping subsequent fires out of all areas once burned. These 
constitute the methods now followed within the national forests of Washington 
and Oregon to secure the reforestation of lumbered areas.—Gero. D. FULLER. 
Plants of acid soils.—A method of determining the acidity or alkalinity 
soils were classified for the purpose of this’ study as “superacid,”’ “mediacid,” 
“‘subacid,” and ‘‘minimacid,”’ containing respectively more than 1000 times 
the acid of pure water, 100 to tooo times, 10 to 100 times, and up to 10 times, 
with a similar evaluation of the alkaline soils. It is then pointed out that 
oxylophytes may be regarded as plants of mediacid soils and calcicoles of 
neutral or minim e soils. Tables based upon soil tests show tha 
among the heath plants of New England, those of the Pyroloideae are most 
characteristic of subacid soils, while the Ericoideae and Vaccinoideae most 
y reach best development upon mediacid soils, many upon subacid and 
meninnackd polls, and a few upon rset! baer . setdgae & list of neh oot 
vICO opod am Sel ag 
Clintonia borealis, Coptis trifolia, Cornus canadensis, and Linnaea a 
nother list is compiled of plants upon circumneutral soi 
Similar methods applied to the study of certain coat areas also give 
most interesting results.** A strip of land between the pine barrens and the 
salt marshes of New Jersey and populated by plants characteristic of the 
upland woods of the northern part of the state showed a specific acidity of 
ro or less, so that the soil may be classified as circumneutral. On closely 
associated areas are found plants which grow elsewhere in southern New 
Jersey only in the sand barrens. These soils, in spite of their proximity to 
the salt marsh, showed a specific acidity of 300, or practically the same as 
that of the pine barren sands themselves. The border of some salt marshes 
on the Massachusetts coast showed plant associations usually found inland 
on peat or wet sand, and again tests proved the soil to be strongly acid. The 
explanation of these strongly acid soils bordering the alkaline salt marsh 
areas is that from the sea water drawn by capillarity into the soil the bases 
3 WHERRY, Epcar T., Determining soil acidity and alkalinity by indicators in 
the field. Jour. Wash. Aca id. Sci. 10:217-223. 1920. 
oil acidity and a field method of its measurement. Ecology 1:160-173- 
pl. 1. 1920. 
24. Soil tests of Ericaceae sit ~~ ape cagrsnete families in northern 
Vermont and "New Hampshire. Rhodora 22:33-49. 
———, Plant distribution se salt ae in relation to soil — 
Ecology 1: par 1920. 
