Valuing grass-land.
The general method of estimating value is to consider the yield per acre, without any special reference to the feeding-value of the crop. In the case of hay grown for sale, this method may be the correct one, but it is not necessarily so in the case of a pasture. The true value of a pasture is based on the amount of " net available nu trients" which it produces per acre; or, in other words, the influence of the herbage on the animal that con sumes it. By this method of valuing, the pasture which produces the most beef, mutton or milk, would be ranked as of the most value.
The following are some of the factors that have a direct influence on the value : (1) The character and condition of the soil. Certain soils, owing to their peculiar properties, are emi nently fitted for the production of good quality grass. One of the most important of these properties is the ability to hold sufficient moisture.
(2) The method of management.
Manures and fertilizers influence the total yield and quality of the herbage and the time of growth. They may prolong the period of growth of a short lived pasture. They tend to reduce the variation in yield due to favorable and unfavorable seasons. At Rothamsted, England, during a period of twenty years, the 2, ields of hay from unfertilized grass land varied from 4,368 pounds per acre in the most favorable season, to 892 pounds per acre in the least favorable one. On well-manured grass land. alongside, the yields varied from S,960 pounds to 4,480 pounds during the same period. Mismanaged land does proportionately worse in unfavorable years when produce is high. In other words, land in good condition gives more uniform yields and the good farmer is more independent of seasonal variations than the poor farmer.
By intense cultivation and heavy fertilizing and seeding, Mr. George M. Clark, of Higganum, Con necticut, reports enormous yields of hay (Fig. 660). He says : "Last year (1906) my timothy and red-top field contained eleven acres, and the alfalfa field three and one-half acres. The eleven-acre field produced
in two crops eighty-one tons of well-dried hay, and the three-and-one-half-acre field produced twenty one tons in four crops, making one hundred and two tons from the fourteen and one-half acres. The seven-eighths - acre piece is a part of the eleven-acre field, and produced its usual crop of over eight tons, in two crops, each year, or one hundred and forty-seven tons in seventeen years, at one seeding." (3) The number and character of the plants per acre. Although it is not known how much empha sis can be laid on these factors, it is conceivable that they are of some importance. It is certain that an animal must not have to travel too far to secure its food if we would have it fatten, and that a certain number of plants must be maintained per acre for profit.
As to the character of the plants necessary for a good pasture, there is little data. Investigations conducted in the United Kingdom, by Drs. Fream and Carruthers, for the Royal Agricultural Society of England, show that there is not necessarily any relationship betweeen the botanical composition of the herbage of a pasture and its feeding value. In some of the best pastures the cultivated grasses might constitute as little as 11 per cent of the herbage or as much as 100 per cent ; legumes might constitute 38 per cent or be absent ; miscel laneous plants, so-called weeds, might be absent or constitute 89 per cent by weight of the total yield. Two pieces of grass-land may have the same grasses in the same proportion and yet the feeding value be very different. On the other hand, two pieces may have entirely different kinds of grasses and yet the feeding value be about the same.
Individual plants of the same species vary to a remarkable degree in duration, yield and other characters, and it is readily conceivable that the variation in feeding value is as marked as it is in other characters. The selection and propagation of desirable individuals is now attracting the atten tion of plant-breeders.