The water‐soluble carbohydrates of grasses. IV. The effect of different levels of fertilizer treatment

Established plots of four perennial grass species, rye‐grass (two strains), meadow fescue, timothy and cocksfoot were dressed with a balanced fertilizer at the rate of 0, 2 and 4 cwt./ acre at the start of the growing season and after each cut at the height of 8–10 in. The soluble carbohydrate (free hexoses, sucrose and fructosan) and the crude protein contents of the grass at each cut were determined and estimates of the yield of dry matter recorded. Increasing the amount of fertilizer led to (a, an increase in the weight of dry matter per acre and the number of cuts taken, (b, an increase in the protein content and the average weight of protein per acre at each cut and (c) a decrease in the content of soluble carbohydrates, particularly the fructosan fraction. The average weight of soluble carbohydrates produced per acre at each cut was least at the highest rate of fertilizer application. The stimulating effect of fertilizer appeared therefore to result in the utilization of sugars for leafy growth at the expense of carbohydrate storage in the form of fructosan.