246 HORTUS GRAMINEUS WOBURNENSIS. 



seeds, sown on an acre of land, will (omitting fractions) afford but 

 two seeds to every square inch — while the most productive an- 

 cient natural pasture examined, had seven plants to every square 

 inch. But the statements respecting the seeds are founded, it is 

 evident, on the supposition that every seed vegetates and produces 

 a plant, and that the seeds are all equally spread over the surface : 

 but, as before observed, there are more circumstances than one 

 which interfere to prevent the successful vegetation and equal dis- 

 tribution of all the fine seeds of grasses individually considered, 

 and which may be sown at any one time. The seed of cock's-foot 

 is often defective, the perennial red clover has frequently many 

 abortive seeds, and the meadow-foxtail seed is generally so bad as 

 to afford but one fertile seed out of three : to obtain a required 

 number of plants on a given space of ground, from a known 

 quantity of seed, a pretty large allowance must therefore be 

 made to the seed, in order to meet those circumstances adverse 

 to certain vegetation in every instance, and equal distribution of 

 the plants. 



An examination of the most productive pastures shews, that 

 when from twelve to twenty different species of grasses are inti- 

 mately combined together, six or seven plants to the square inch 

 of surface are not too many. The turf from the irrigated meadow 

 afforded the greatest number of plants, being twelve plants to a 

 square inch ; the predominant species in this turf was the Poa tri- 

 vialis, the seedling plants of which are small, and, along with the 

 plants of Bromus arvensis* derive their support, in irrigated mea- 

 dows, more from the water than the soil ; few of the roots of these 

 species had much hold of the ground, and a great number of the 

 plants were rooted merely among the crowns of the roots of 

 the other species of grass which composed this turf. The state- 

 ments brought forward relative to pastures artificially formed of 

 rye-grass and clovers, and those facts connected with the number 

 of plants of grasses which are found to occupy a given space of 

 oround, when one species only of grass is cultivated by itself, 



* Tlie Bromus arvensis, an annual grass of little merit elsewhere, is here valu- 

 able ; the seeds ripen at the end of June, or in July, according to the season, and 

 other circumstances which peculiarly influence the economy of annuals iu this par- 

 ticular. The seeds vegetate quickly after falling from the husks, and the plants 

 make rapid progress, and furnish the most luxuriant foliage for sheep and cattle 

 that is to be found in meadows, during late autumn, winter, and early spring 

 herbage. 



