WEEDS AND THEIR IDENTIFICATION.
CONTINUED.
ESMOND ATKINSON,
Biological Assistant.
VIPER’S BUGLOSS
(ECHIUM VULGARE).
General Description.— Viper’s bugloss, which belongs to the same family as the . borage and forget-me-not, is . one of the most easily recognizable of all our weeds from its very conspicuous brilliant blue flowers, which in places where it is abundant form quite a feature in the landscape. The plant is generally ranked as a biennial in other countries, but in New Zealand it very often assumes the perennial habit. The roots are stout and tapering, and penetrate deeply into the soil. Young plants , bear a crowded rosette of radical leaves, but, as the flowering-stems develop, this rosette character becomes less obvious. The stems are not numerous as a rule, nor are they much branched normally. The cutting of the stems, however, stimulates the formation of branches to a marked degree, and plants may often be seen with their original flower-stalks cut off low down, but with densely clustered secondary stems springing from below the cut, showing the futility of attempting to prevent seeding by merely cutting off the stems. The leaves are long and narrow, pointed at the tip, and, like the stems, are covered with raised points or tubercles and -with numerous whitish bristly hairs. The main stem bears a number of flower-spikes, which (as is usually the case in the forget-me-not family) are onesided and incurved at the tips. Examination of a plant in full flower will show that each spike bears buds at its tip, then open flowers, and finally, at the base of the spike, ripening fruits. Late in the season, through the elongation and straightening of the flower-spikes, the plant alters a good deal in appearance. The buds are rosy-pink, but the colour changes as development proceeds, until in the -fully expanded' flower it is a deep clear blue. Each flower consists of a five-lobed bristly calyx, and a five-lobed irregularly funnel-shaped corolla from the throat of which spring the five stamens. The ovary is four-celled, and bears a long slender style which is two-lobed at the tip. There are four seeds, which after the corolla has fallen remain enclosed in the calvx. The seeds are
brownish, | in. long, irregularly top-shaped, with an angled inner face and a convex outer one, and with. a hard and rough surface.
Distribution, &c.— Viper’s bugloss (which is included in the Third Schedule of the Noxious Weeds Act) is widely distributed throughout New Zealand, though it , may be almost absent from large areas. The Province of Marlborough is at present its chief stronghold, and it has there - been declared a noxious weed. It is in that district very abundant as a weed of" roadsides, dry' river-beds, and similar waste places.. Its importance to the farmer, however, lies in its being, an aggressive weed of pastures, particularly where the soil is loose and dry. Owing to the harsh and bristly character of the leaves and stems, stock will not touch the plant, and where it has obtained a hold.’ it will soon crowd out large areas of valuable grass. Where this takes place ploughing and cultivation should be resorted to. At most times of the year viper’s bugloss possesses the power of growing from the root after the crown has been cut off below the surface, but during or just before the flowering season this treatment will kill it. Where only small quantities of the weed are present hand-pulling is the most effective way of getting rid of it. If it is troublesome on cultivated land, summer fallowing combined with the liberal use of the scarifier should be adopted as a means of control. The seeds, though not common as impurities, are occasionally found in those of certain clovers. The writer is indebted to Mr. A. Hughes, Fields Inspector, Rangiora, for some of the information contained in the above account, particularly that dealing with the methods for the control of the weed. • INKWEED (PHYTOLACCA OCTANDRA). General Description. —This plant, which is also known as pokeweed and red-ink plant, belongs to a small and little-known tropical family which is chiefly American in distribution. Inkweed is a soft-wooded shrubby plant, forming bushes 4 ft. or 5 ft. high and about the same in diameter. The branches, which are brittle, bear numerous leaves 3 in. or 4 in. long by in. or more in width. The flowers from their small size and greenish colour are inconspicuous, and are arranged in upright tapering spikes which arise singly from the leaf -axils. An individual flower is of simple structure: the petals are absent, but there are five sepals, in the centre of which is an eight-lobed ovary surrounded by a ring 'of 'eight stamens which are arranged alternately with the cells of the ovary. After fertilization has taken place the ovary enlarges enormously, gradually losing its octagonal shape until, when fully ripe, it forms a berrylike fruit deep purple or almost black in colour, and in shape
round when seen from above, but much flattened at top and bottom. The fruit is filled with a rich reddish-purple juice, which has been used for ink, and which has consequently given the plant its popular names. The fruit-spike is much more striking than the dullcoloured flowers, and it hardly, becomes less conspicuous when the falling of the fruits reveals the persistent calyx-lobes, which have by this time become bright red in colour. The seeds, of which there are eight in each fruit (each seed corresponding. to a cell of the ovary), are about 1% in. in diameter, round in outline but with a projection on one side, roughly lense-shaped, and with a brilliant, shining black surface. Distribution, &c. —-Inkweed is very abundant from ■ the 'Kingcountry northwards, and though it has spread as far south as Wanganui, it is in the north that it attains the greatest prominence. It is one of the most conspicuous weeds of the Auckland Province, on account of its large size and handsome appearance. For many years it has been classed as a weed merely of waste ground or, at most, of ground that could only be partly utilized ; but of late its presence on new bush burns has become more and more pronounced, especially in the King-country and in the districts north of Auckland. The rapid appearance of inkweed in new bush-burn country has led many farmers to the conclusion that the seed must have been introduced on to the land in the grass-seed mixtures used. There is no reason whatever to show that this is the case ; on the other hand, there is abundant evidence . that birds are . the agents responsible for the introduction of the plant into new areas. The juicy fruits of inkweed are very attractive to many kinds of birds, and the seeds, with their hard and shining covering, are not prevented from germinating by their passage through the alimentary canal.; On bush burns where ink weed makes its appearance in the first season, heavy stocking with young cattle is to ' be recommended, as such treatment tends to crush out the plant before it attains too great a height to be trodden down. Although inkweed is recognized as possessing poisonous properties,* there is little likelihood of its proving dangerous to stock, which are not known to touch the plant. * See article on this subject in the Journal for October, 1913, page 369.
Sixteen selections of’ Scotch vetches were grown at Moumahaki Experimental Farm during the past season. One of the selections gave outstanding results, the seed being evenly coloured and larger than the usual market sample, giving approximately two thousand seeds to the pound. It is intended to propagate this selection during the ensuing season.
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Bibliographic details
New Zealand Journal of Agriculture, Volume XII, Issue 5, 20 May 1916, Page 381
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1,280WEEDS AND THEIR IDENTIFICATION. New Zealand Journal of Agriculture, Volume XII, Issue 5, 20 May 1916, Page 381
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