HEAVY SEEDS. 109 
not thrive well on a trefoil layer unless they have access to 
plenty of other feed; indeed, it is sometimes difficult to get 
them to touch tréfoil at all. 
Like suckling, trefoil is a biennial, but as it seeds itself freely, 
it becomes almost perennial. Thus 1 Ib. to 2 Ib. of the seed 
may be added to permanent mixtures, and it is so cheap that 
its cost need hardly be taken into consideration. On account 
of its uncertain nature we sow 2 Ib. to 3 lb. of white clover, 
and 2 lb. to 3 lb. of red suckling with an alternate trefoil ley ; 
the red suckling in case the spring should turn wet and cold, 
the white clover to form a bottom in case of heat and drought. 
To this we add 6 lb. of perennial ryegrass, or 20 Ib. of Italian 
ryegrass, and as trefoil neither spreads nor tillers, it is desirable 
to fix the amount of it at 30 lb. which proportions the 
mixture, 
The seed is slightly smaller than red clover, shaped like a 
pig’s kidney, and can easily be distinguished from clover seed. 
In colour it is a-greenish yellow, but turns brown with age, 
ripeness, or weather. 
The ripest and best samples are those which are neither too 
brown nor too green. 
The plant is fibrous rooted, biennial, and in appearance 
resembles red suckling. It is indigenous to many places, and 
there exists a variety of the same species, an annual of inferior 
quality ; but this smaller variety is easily detected, as its seeds 
exude a powerful aromatic smell quite different to the Medi- 
éago lupulina. his variety can hardly be called a weed, as it 
is comparatively harmless, and when present on corn stubbles, 
quite makes up for the objection it may prove to the growing 
corn crop by the after feed it produces, 
In weight, a bushel of trefoil scales 66 lb., each pound 
containing about 300,000 germinating seeds. 
