24 BULLETIN 4, U. S. DEPARTMENT OF AGRICULTURE. 



not necessary to determine their acidity by chemical analyses. The 

 acid condition of the soils may be recognized by noting the kind of 

 plants growing on them. 



In coves where aeration of the soil is largely prevented by satu- 

 rated moisture conditions during the greater part of the year, the 

 vegetation is entirely made up of plants that are adapted to living 

 in strongly acid soils. The Wallowa mountain lands of this char- 

 acter support a number of locally well-known grasses such as moun- 

 tain timothy (PMeum alpinum), slender reed grass {China latifolia). 

 tufted hair grass {Deschampsia caespitosa), marsh pine grass (Cala- 

 magrostis canadensis) , and tall meadow grass (Panicularia nervata). 

 (See PL VII. fig. 1.) Intermixed with these are a number of 

 sedges, rushes, and weeds, the more common of which are tall swamp 

 sedge (Oarex exsiccata), water sedge {Carex f estiva), wood rush 

 {Juncoides glabratum). cone flower {Rudbedkia Occident alls), and 

 false hellebore (Verairum viHde). (PL VII, fig. 2.) The genera 

 here mentioned indicate, in a general way. an acid soil, though all the 

 species of a single genus do not necessarily prefer sour soils. TVTiere 

 these plants and those of similar habits are found in abundance, and 

 -where the soil remains in a high state of moisture during most of 

 the year, it is relatively certain that clovers. Kentucky blue grass, and 

 even timothy, and indeed all cultivated plants used in this investi- 

 gation, except redtop. will not succeed. Eedtop. on the other hanr 1 

 makes its most luxuriant and prolific growth in these lands. 



Even in some of the better drained acid soils where huckleberries 

 and heaths or willows and alders occur in abundance, redtop is often 

 the most satisfactory species. These plant associations, except pos- 

 sibly in the case of dense stands of huckleberries, usually indicate a 

 less strongly acid soil than the grass and sedge marshes. TThere 

 lands of these types are so situated that drainage is not seriously 

 obstructed, timothy, which is found to succeed in moderately sour 

 lands, is often a valuable species for reclaiming them. All the ex- 

 periments indicate that timothy, next to redtop. will give the best 

 returns on such soils. This is one of the instances where a mixed 

 seeding of redtop and timothy is justifiable. If the soil proves too 

 sour for timothy or too dry for redtop. the chances are favorable to 

 the establishment of one or the other of the species. 



The intensive studies have therefore established: 



(1) That under usual conditions reseeding will be most successful 

 if performed in the fall after vegetative growth has ceased. 



(2) That inexpensive soil treatment either in the form of brush or 

 tooth harrowing or by the trampling of sheep is highly important. 



(3) That in endurance of drought smooth brome grass, timothy. 

 Kentucky blue grass, and redtop grade in the order named from high 

 to low resisting power. 



