40 MASS. EXPERIMENT STATION BULLETIN 380 



the ability to supply herbage during the hot summer as well as during the spring 

 and autumn, is closely associated with the nature of the plant cover. This phase 

 of the pasture problem, like that of grazing management, is relatively new and 

 it is one in which rapid progress is now being made. Therefore, it is not possible 

 at this time to present a full or conclusive discussion. 



Permanent Pasture Species 



The pasture plants most commonly found in permanent pastures are Kentucky 

 bluegrass and white clover in the best pastures; variable percentages of blue- 

 grasses, bent grasses, fescues, and native white clovers, together with a variety 

 of weed species, in the poorer ones. Although the species composition of most 

 poor permanent pastures can be definitely improved by following suitable fertiliz- 

 ing practices, the best that can be hoped for without plowing and reseeding is a 

 good stand of Kentucky bluegrass and native white clover. These two plants, 

 although a good source of grazing during the spring and fall, are invariably a poor 

 source during midsummer. The clover is particularly susceptible to injury from 

 drought, while bluegrass grows very slowly during hot weather. The result has 

 been that permanent pastures reach high levels of production in spring and 

 autumn and fall to very low levels during midsummer. 



Semi- Permanent Pasture Species 



Because of the serious limitations inherent in the common permanent pasture 

 species, a number of other grasses and legumes have recently been used in pasture 

 seedings. In practically all cases with these plants, however, it is necessary to 

 plow and fertilize before seeding; and in most cases, even though the plants are 

 perennial in nature, a good stand will not last for more than three to five years. 

 Consequently the period of maximum usefulness of such pastures is limited and 

 they are called semi-permanent pastures. 



Several of these newer legumes and grasses, have proved to be definitely superior 

 to bluegrass and native white clover. If soil fertility relationships are favorable 

 and the grazing is controlled, total yields of herbage are much larger and, what is 

 more important, seasonal fluctuations in yield are smaller. Production is main- 

 tained at fairly high levels even during the hot summer months when good graz- 

 ing is usually quite scarce. 



Of the newer pasture legumes tried in Massachusetts, Ladino clover has been 

 used with the greatest success over a fairly wide range of soil conditions. In other 

 sections of the country alfalfa is showing some promise as a pasture plant, but 

 because of the nature of the soils the extensive use of alfalfa in Massachusetts as 

 compared to Ladino clover is unlikely, especially as alfalfa lacks some of the quali- 

 ties of a good grazing plant. Many of our soils are shallow with sandy or gravelly 

 subsoils and as such are not well suited to a deep-rooted, strong-feeding crop like 

 alfalfa, while with other soils the water table is too high for satisfactory growth. 

 Ladino clover, which compares favorably with alfalfa in yielding ability, is a 

 surface feeder with large numbers of small roots which develop principally in the 

 plow layer of soil. It is a comparatively simple matter to maintain adequate 

 supplies of mineral nutrients in the plow layer through adequate fertilizer prac- 

 tices, but it is difficult to make up mineral deficiencies in the subsoil layers. 



The newer grasses have been given only limited trials in ]Massachusetts and 

 most of these have been experimental. Of the species thus far tested, brome grass, 

 meadow fescue, orchard grass, and certain types of rye grass appear to show the 

 most promise. With most of these species, particularly with orchard grass, many 

 different strains have been developed, some of which are much more suitable for 

 pasture purposes than others. Many of these different strains are now under- 

 going careful test, seeded alone and in mixtures, and it is likely that plant breeders 

 will produce still better strains as time goes on. Indications are that some superior 



