NATURE NOTES

Press, Volume LXXIII, Issue 21990, 14 January 1937, Page 6 (Supplement)

NATURE NOTES

* Humphrey Hudson has sent a weed from Teddington for identification. '(• Following Dr. P.. W. Hilgendorfs it hook on New’Zealand weeds, I will call it red shank, but it has various other names such as Lady’s Thumb, Persicaria, Smart-weed, =:' Knot-weed, and Willow-weed. Its ‘.botanical name is Polygonum, persicaria, the first name coming from *• -the Greek “polus,” many, and v **gonu,” a. knee, from the conspic- - upus knees or nodes on the stem.\ , \ Red #hank is found naturally in and Asia and was probably introduced here from England. In ’ dry districts it is usually fo t und -f: duly _on the sides of ditches,; or, in damp shady .corners of £. ; ' gardens. In swampy, country or in with a heavy rainfall, such fcJasthe West Coast, it may be found g, everywhere. ' ...... The plant varies in appearance compact one, a few inches |>,4iigh when it is growing out in the feX open, to one with -straggling stems feet long when it is growII iinjg'ftmong other plants. The stems v- ate round and shiny, with swollen Joints. The colour is red or pur--5,' plish-red varying in depth with the amount of light. ft r At first glance the leaves might Spile .said-'to look like willow leaves, .. hut.closer examination shows them ; ~ to liave In most cases a dark irt‘Regular blotch in, the.middle. This is really the best identifier cation character.' A further point look for is the sheath or stipule l?V afthe base of the leaf. This stipule - Which is hairy and edged with ; ~ longer hairs forms a tube at the , ■’ Junction of leaf and stem. _ The flowers, which are pink or ‘ 'greenish, and very , small individ-

RED SHANK

(By L McCaskill)

ually, are borne in dense clusters at the ends of the branches. There are usually six stamens, but the number of styles is sometimes two, occasionally three. If there are two, then the nut which develops will be flattened; if there are three styles, then a triangular nut like a dock-seed will be: found. Red shank is a serious weed in New Zealand in damp cultivated grounds There it may interfere with the establishment of a young pasture, or, if growing in a cereal crop, it may choke the young plants; The only means of control is thorough cultivation In time to prevent the formation of seed. Lady’s Thumb was the name used by country people in England for hundreds of years., According to folk-lore, the Virgin Mary used the leaves of red shank to make an ointment. On one occasion she sought for it without success and came across it only when it was too late. She is then said to have reduced it from the rank of a useful herb to that of an ordinary weed.. As the old couplet said:— ‘‘She could not find in time Of need And so she pinched it for a weed;” and the miirk ol her finger or thumb is still to be seen in the dark blotch on the leaf. Specimens of insects or plants are invited from readers. The conditions under which such specimens are found as well as the locality, should be clearly stated. •’ It is necessary to state whether the specimen, if an insect, was dead or alive when it was found.