Clover-Seed and its Impurities. 
•!:;!> 
sample. In a former Number of the ' Journal ' (vol 
series, p. 253) I described at length the structure 
of this injurious parasite. 
The Broom-rape (Orobanche minor 
itself to the roots of the clover, and 
sends up a slender, leafless stem from 
(! to 2-4 inches high, which is at first 
of a yellowish purple colour, and 
becomes ultimately brown. The 
whitish flowers are followed by ob- 
long capsules full of numerous mi- 
nute seeds, with a thick pitted cover- 
ing of a dark-brown, almost black, 
colour. 
The seeds of these two parasites are 
samples. The Broom-rape has, 
to the clover-crop in 
ix., second 
and habits 
attaches 
Orobandifi minor. 
Broom-rape. 
Sutt. 
chiefly found in foreign 
in some years, been very de- 
Holland. It has chiefly 
structive 
appeared in this country in the crops of Norfolk, Kent, and 
Surrey. 
The longevity of the small seeds of Dodder and Broom-rape 
is remarkable. When ploughed into the ground they often 
remain in a living condition in the soil till a crop suitable for 
their support is grown in its course in the field. They then 
re-appear. Indeed, when in the course of cultivation the plough 
brings these seeds again to the surface, they may sometimes be 
found, in the absence of suitable plants, attacking other crops 
which it is not their nature to live upon, as in the case of the 
Dodder attacking a crop of turnips which came under my notice, 
and the same weed has been several times observed attacking 
wheat. These seeds retain the power of germination for at 
least four or five years when buried in the soil ; for it has been 
observed that when the Dodder appeared on plants of clover 
in ley-wheat, it re-appeared when in due course the field was 
sown with clean clover. When, therefore, a growing crop is 
infested with either of these parasites, it is important that the 
cultivator should not plough them into his land, but ensure their 
complete destruction by burning them. 
During this summer (1877) I found the Dodder abundant in 
clover fields around Heme Bay ; and in one field the Broom- 
rape had appeared. I learned from the bailiff that he had not 
noticed this plant in previous years. Unaware of its nature, he 
had not interfered with its growth. He had noticed it in the 
first crop, though it was not at all abundant ; but after cutting 
the clover the minute seeds, now fully ripe, were scattered and 
unexpectedly sown. The parasite reappeared in such quantity 
in the second crop that patches of the second crop were com- 
VOL. XIII. — S. S. 2 II 
