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vine (Z. pandurata) sometimes has a root that attains the size, 
and occasionally the form, of a boy’s body, and weighs thirty- 
five pounds. Belonging to the same family are the two species 
of Convolvulus, and all are related to the sweet potato and yam, 
which are grown for their large roots. All three of these weeds 
are eradicated with great difficulty because of the perennial nature 
of the large, deeply-buried roots. The Afocynum is perhaps the 
least abundant of the weeds named above, but is remarkable for 
the size and persistence of its roots when once established in cul- 
tivated ground. The dandelion is familiar to all, and its tap-root, 
enormous for the size of the plant, rivals that of the burdock, a 
member of the same great family of plants. The Canada thistle 
has a root system peculiar to itself and renders the plant particu- 
larly difficult to eradicate, the depth to which the long roots 
descend in the rich loose soil being many feet. It only remains 
to say that the St. John’s wort is not an easy pasture weed to 
pull on account of its deep anchorage, and the dock is likewise 
noted for its size and length of root. 
The list of big-rooted biennials consists of: Medicago lupu- 
fina, L. (nonesuch), CEnothera biennis, L. (evening primrose), 
Daucus Carota, L. (wild carrot), Pastinaca sativa, L. (parsnip), 
Dipsacus sylvestris, Mill. (teasel), Cynoglossum officinale, L. 
(hound’s tongue), Echium vulgare, L. (blue-weed), Verbascum 
Blattaria, L. (moth mullein) and Verbascum Thapsus, L. (mul- 
lein). For the size of its aerial portion the blue-weed or viper’s 
bugloss is perhaps the largest rooted biennial, but this is closely 
followed by the carrot and parsnip among the lower weeds, and 
by the evening primrose, teasel and the mulleins for the larger 
species of the group. From the biennial nature of these plants 
it follows that if they are kept from seeding the land will soon be 
tid of them. 
The weeds having tap-roots ranking in the second size, num- 
ber twenty-two as follows: perennials, five; biennials, one, and 
annuals, sixteen, thus showing a large number in the last group. 
The perennials are: Malva rotundifolia, L. (mallow), a low plant 
with a stout, woody tap-root; Passiflora incarnaia (passion 
Fine), a deeply rooting noxious weed of the Southern States, 
Cichor ium Intybus, L. (chicory), a tall and deeply-anchored 
