47 
The seed of wayy hair-grass (Aira flexuosa, L.) is often sub- Adulterations. 
stituted for that of Yellow oat-grass. The Aira is very common on 
dry, barren soils, on sands and heaths, on wood-clearings, etc. It 
produces a tuft of bristle-like leayes, and slender culms, 8—12 inches 
high. The produce has no value as fodder, and sheep will scarcely 
touch it. In July and August the seed is ripe, and about this time, 
the seed merchants buy it at a cheap rate. The seed of Wavy hair- 
crass (fig. 20) is easily recognised, when examined by a lens. ‘The 
ae es 
pales are reddish-brown and much darker than those of Yellow oat- 
orass ; a bent awn springs almost from the base of the lower pale. 
Its seed is about twice as heavy as that of Yellow oat-grass. 
Quite recently the seeds of Calamagrostis arundinacea, Roth. 
(fig. 22) have come into the markets as Yellow oat-grass. This is 
recognised by the ashy-grey colour. As in Yellow oat-grass, the 
bent awn springs from the back of the lower pale, and the stalk is 
Fig. 20. hairy. These adulterants are never mixed with one another nor with 
Wavy hair-grass. Yellow oat-grass seed. The pure Atra or the pure Calamagrostis 
5 g 
Aira flexuosa, L. 
a. False fruit, natural size ; 
b. the same, dorsal surface ; 
c, the same, side-view 8. 
seed is brought into the market, and sold as that of Yellow oat-grass. 
2 2) 
Seed and amounts to be sown. ‘he average purity is 34.4 °/o Seed quality. 
and the germinating power 37 °/o. Good seed should have 40 °/o 
purity and 40 °o germination = 16 % of pure and germinating seed. 1 Ib. of good seed 
contains on an average 2,045,000 erains, of which 327,260 are pure and germinating. The 
Fig. 21. 
Yellow oat-grass, Avena flavescens, L. 
False fruit: — a. natural size, 
1 eT oan Ae 
£ acre would then be about 
weight per bushel is 5 to 
5'/e Ibs. An acre of ground 
requires 29 lbs. of seed 
containing 16 °/o pure and 
germinating = 4.64 lbs. of 
pure and germinating seed. 
The price per lb. is 2s. 6d. 
the average cost of seed per 
Quantity of 
seed per acre. 
£ 3.12s. 6d. Sinclair says: 
>I have sown the seeds of 
this grass in almost every 
month of the year, and 
after making due allowance 
for the state of the weather, 
al. b. 
the third week in May, Fig. 22. 
and from the first week Calamagrostis arundinacea, Roth. 
of August to September, False-fruit : — a. ventral surface, with 
were evidently the best«. the stalk, b, side-view. 
Sown alone, the produce is small, and the grass very 
loose and thin. 
