ch. vni] Yellow Oat-grass 139 



purely a pasture or meadow grass, but as a principal constituent 

 of the turf of shaded park land and pleasure grounds, especially 

 where the elevation is high or the soil poor or variable. Its rich 

 green foliage also adds to its value for this purpose. It is less 

 suitable however for playing grounds as its rather broad, soft, 

 hairy leaves hold dew and moisture too readily and the plant does 

 not produce a turf that will "wear" well. 



Commercial Seed. 



Practically all our seed has hitherto come from Central Europe 

 and as it is mostly hand-collected its cost is high. Sheep's Sorrel 

 (Rumex acetosella) and Woodrushes (Luzula campestris, mostly) 

 are the usual weed impurities (see Figs. 153, 154 and 175). The 

 seed of a closely allied species known as Puel's Vernal-grass 

 (A. Puelii, Lam.) is occasionally used as an adulterant or even 

 entirely substituted for the real article. This plant is an annual 

 and quite useless for cultivation. The seeds of A. Puelii are 

 covered with hair which is paler in colour and less silky than 

 in A. odoratum while the awns are slightly longer and finer. 



Well cleaned samples of Sweet Vernal-grass seed will not con- 

 tain more than five per cent, of chaff and less than one per cent, 

 of weed impurities. The Purity of good samples should exceed 

 90 per cent, and the Germination should reach 70 to 80 per cent. 

 in 20 days. 



Avena flavescens, L. 



For Botanical description see p. 68. 



Yellow Oat-grass is indigenous to the temperate parts of Europe 

 and Asia and to northern Africa. It is much less frequent in 

 Scotland and Ireland than in England where it is common in the 

 drier pastures and meadows. It thrives at high altitudes and is 

 a good drought-resisting plant. Its most luxuriant growth is 

 attained on moderately moist calcareous or marly soils, but even 

 under the best conditions its yield is only moderate. Full develop- 

 ment is reached by the second or third year after sowing. It is 

 essentially a "bottom growth" grass and the bulk of its yield is 

 produced in the middle of summer in Britain. Its produce is entirely 

 free from coarseness and both cattle and sheep are fond of it. 

 Owing to the high price of its seed its use is necessarily restricted, 



