Annual Report for 1890 of the Consulting Botanist. 835 
and other conditions are favourable. If hand-pulling is not possible, 
the duckweed should be cut when in flower to prevent seeding. 
Several inquiries have been made as to devil's-bit scabious, not 
that it had produced any injury to stock, but it had so greatly in- 
creased as to displace the useful plants of the pasture. Being a 
perennial plant with a short thick root, giving off numerous branch- 
ing fibres, it cannot be eradicated except by spudding or careful 
hand-pulling. The greater knapweed, which has also been com- 
plained of, must be similarly treated. 
Bitter-sweet caused injury to several cows in a field where it 
was abundant in the surrounding hedge. It is an active poison, and 
should not be allowed to grow where cattle feed. It must be dug 
out, but, as the plant rarely occurs in any abundance, this is not a 
serious work. The water figwort, though it cannot be said to be a 
dangerous plant, may nevertheless produce some irritation in the 
digestive canal, and should consequently be eradicated. Another 
weed, often found associated with the water figwort, has a very sus- 
picious appearance, and is often credited with injury, but without 
just cause. I refer to marshwort, an umbelliferous plant with a 
straggling stem, freely rooting at the joints, and producing its 
numerous small white flowers on short stalks at the joints opposite the 
leaves. This plant is often gathered with watercress, and is eaten 
with impunity. It is very common along the margin of ditches and 
in marshes. Queen of the meadow is a common weed in meadows, 
which is freely eaten when its leaves are young without any injury. 
Complaints have been made of the presence of the greater burnet 
in clover. This is an impurity occasionally found in clover seed. 
There is no difficulty in separating it because of its difference in 
size It is sometimes eaten by stock, but it is not a favourite food, 
and clover seed mixed with it should be rejected. 
The large Siberian melilot or Bokhara clover has appea>;ed in 
several places among the lucern. This great melilot was introduced 
some years ago as a useful fodder-plant producing a large amount 
of food, but it was found to be too watery when young, and too 
woody when old, and its cultivation has been discontinued. 
Serious cases of injury to crops by the attacks of parasites have 
been brought under my notice. In several districts dodder has 
been very destructive to the clover. The parasite has no doubt in 
each case been introduced with the seed. The sale of clover with 
dodder is inexcusable, because, from the different sizes of the two 
seeds, a sieve with proper meshes will easily separate them. No 
clover seed, at least no alsike or red clover, should be bought without 
a guarantee that it is free from dodder, and then compensation 
could be obtained if unclean seed were supplied. When the dodder 
appears it should be completely removed and burned, and a space of 
at least a yard all round the affected plants should be cut clean 
down and removed ; if this is not done some outlying fragments 
of the dodder will re-establish themselves and spread the injury. 
Complaints have also been made of broom rape, another parasite, 
the seed of which is introduced with the clover seeds. It is much more 
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