The Red Spider. (Tetranychus telarius.} 



VI., Fig. 3.) 



This little creature is most destructive to many of the 

 crops of the farmer, gardener, and fruit-grower. Its mischief is 

 frequently attributed to other causes, as it is so small that it 

 escapes observation. Thus, its action upon hop plants, causing 

 the leaves to turn yellow and to drop prematurely, was formerly 

 supposed to be due to hot dry weather, and was termed " fire- 

 blast." In Germany this is called kupfer -brand copper- 

 burn because the hop leaves become copper-coloured, arid, us 

 in England, is commonly held to be caused principally by hot 

 sunshine. It is true that this affection of hop plants is always 

 much worse in hot seasons, and rarely shows itself in any other ; 

 but this is because heat and drought are essentially favourable 

 to the red spider. In 1868, 1872, and 1885, there were many 

 acres of hops quite ruined by the red spider. The leaves fell off 

 from the bines, and not a hop was picked. During the last few 

 years damson trees have suffered severely from its attack. The 

 leaves have turned yellow in July and August, and the fruit has 

 not been able to develop and ripen properly. This has caused 

 great losses in Kent where damsons are extensively cultivated. 

 Gooseberry bushes have also been similarly affected by red spiders 

 in the last few years. Their leaves have suddenly turned yellow 

 and have fallen to the great detriment of the fruit and the bushes 

 themselves. Great complaints of this attack upon gooseberry 

 bushes were made by growers in Kent, Cambridgeshire, Worcester- 

 shire, and other fruit-producing centres. A large grower, 

 writing on April 22nd, said : " already at this early date the 

 leaves of many of my gooseberry trees are covered with red 

 spiders. This is the third year o f the attack, and most of 

 my trees are in their prime, and must, I think, be ruined 

 unless I can do something to stop it. I am really quite 

 disheartened, the trees are full of young gooseberries, and 

 continually have every care and attention." 



It is well known that red spiders are equally destructive to 

 vines out of doors, as well as in hothouses, also to French and 

 scarlet runner beans. A species of Tetranychus, closely re- 

 sembling Tetranychus telarius, attacks lime trees. This summer 

 lime trees in many parts of this country were attacked by it. 

 The leaves turned yellow in August and many of them had 

 fallen quite early in September. 



The red spider is becoming a common pest in fruit plantations 

 in England. It has spread rapidly in late years, being con- 

 veyed with young trees, suckers, and cuttings from plantation 

 to plantation and from country to country. Mr. Cooke, the well- 

 known entomologist, and late chief Executive Horticultural Officer 

 of California, wrote as follows concerning this : " The red mite 

 commonly called the ' red spider,' may be said to be a universal 



