76 



IRISH GARDENING. 



Great care must be taken in handling either of 

 these washes on account of their poisonous pro- 

 perties. Never eat vegetables which have been 

 grown beneath trees sprayed with lead arsenate or 

 nicotine until at least a month has elapsed since 

 the application in the case of the former, a fort- 

 night in the case of the latter. The same applies to 

 tlie picking of green gooseberries from bushes 

 which have been sprayed with arsenate of lead 

 to kill the false caternillars of the Gooseberry Saw- 

 tiy. 



Lead arsenate and nicotine can only be obtained 

 from firms licensed to sell poisons. If supplies 

 cannot be procured from a horticultural sundries- 

 man, the local chemist should be asked to obtain 

 them. In any case the " Poisons Book " must be 

 signed in compliance with the " Sale of Food and 

 Drugs Act." 



The above washes may be used to spray all 

 iiianne of fruit trees. — JoKntaJ of Board of Agri- 

 culture. 



Friends and Foes of Allotment 

 Holders^ Crops. 



Apart from the principal insect pests which have 

 been referred to in previous notes, and some few 

 others of less common occurrence, there are other 

 enemies or diseases which affect the crops grown 

 on the allotment. 



Some of these diseases, such as the damping off 

 disease, affect the plants mainly while they are 

 still in the seedling stage, while other diseases 

 affect the plants at different stages in their de- 

 velopment, whenever weather and other condi- 

 tions are favourable to the disease. Certain of 

 the diseases have a tendency to affect one part of 

 the plant only, while other diseases are able to 

 affect practically the whole of the plant. 



Diseases in plants are mainly brought about by 

 Fungi, which are more or less microscopic in size. 

 Fungi are plants of comparatively simple struc- 

 ture; they do not possess chlorophyll (the green 

 colouring matter of ordinary plants) and are not 

 able to manufacture sugar and starch under the 

 influence of sunlight as do plants which possess 

 chlorophyll. 



The Fungi therefore obtaiir their food already 

 manufactured, feeding either- on living plants or 

 animals or dead plants or animals, or iheir re- 

 mains 



If we take for an example one of the larger 

 Fungi, such as the common mushroom, we find 

 that above the ground the mushroom— as it is 

 used— consisting of a stalk, surmounted by a cap, 

 on the under side of which are to be seen a number 

 of thin plates or gills, which are pink in the earlier 

 stages of development (in the edible mushroom) 

 and brownish or even black as maturity is 

 reached. If one of the brownish mushrooms is 

 placed over a piece of paper— gill side down— on 

 a sunny day, and left for a few hours, a quantity 

 of brown, dust-like material will be found on the 

 paper. If this dust is examined under a good 

 microscope it will be seen that the mass is made 

 up of minute granular bodies. These are called 

 spores and given suitable conditions the spores 

 will germinate or begin to develop, forming 

 whitish thread-like structures known as mycelial 

 these structures are the so-called vegetative part 

 of the plant ; they gather the food material from 

 the media m which they live; they are to be found 



at the base of the mushroom ramifying through 

 the soil. After a time these threads join together 

 and give rise to the special branches or " mush- 

 rooms," which are known as the spore bearing 

 or reproductive organs. The nature of these 

 organs and of the spores borne on them differ 

 considerably in the different' groups of Fungi 

 which cause plant diseases. While in the mush- 

 room sexual spores are not developed, in most 

 diseases they are. We have, in fact, at least two 

 distinct types of spores— the so-called summer 

 spores, which, as a general rule cannot withstand 

 prolonged dryness or extremes of heat. By means 

 of these spores the various diseases spread 

 during the summer or growing season, and the 

 so-called winter spores, which are more hardy, so 

 to speak, and through which in many cases the 

 disease carries on from season to season. In quite 

 a number of cases also the mycelium is perennial, 

 and plants become affected through its develop- 

 ment. 



Damping off Disease.— One of the principal 

 diseases affecting the crops grown on the allot- 

 ment, especially where the holder possesses a 

 garden frame, is the damping off disease. 



This disease usually occurs where the seeds have 

 been sown too thickly, and where thinning out 

 of the seedlings has been unduly delayed Also 

 when overhead watering has been indulged in 

 too freely, when the seed bed has been over- 

 shaded, badly ventilated, improperly drained or 

 over-warm or cold, as the case may be When 

 this complaint attacks the plants they topple 

 over m a rather characteristic manner and soon 

 rot away. If the diseased seedlings are examined 

 under the high power microscope, the threads or 

 mycelia and the spore-bearing branches will 

 easily be seen. When one or more plants are 

 artected the disease soon spreads by means of 

 these to other plants until the whole lot very 

 often dies from the disease. To check the de- 

 velopment of the disease the seeds should first 

 ot all be sown under healthy conditions, put into 

 properly drained beds or boxes, sown thinly, 

 thinned out early, watered with extreme care" 

 avoiding anything in the nature of over-watering 

 (especially such as by saturating the foliage a't 

 night and then closing the frame or ventilator) 

 keeping the plants freely ventilated and exposed 

 to full sunshine. 



By partially sterilising the soil either by steam- 

 ing or pouring on boiling water before the seeds are 

 sown many of the spores of the disease usually 

 found m the soil will be killed. 



Club-root or Finger and Toe Disease —A dis- 

 ease which is very prevalent in Turnips, Cabbages, 

 Cauliflowers, &c., in old gardens, on heavily 

 manured land, and on sour soils or where the 

 soil IS lacking in lime is the one known as Club- 

 root or Finger and Toe. 



As is well known this disease affects the roots 

 of such plants, causing the development of the 

 curious swellings from which the disease gets its 

 name. 



These should be distinguished from the other 

 more globular swellings found on the stems which 

 when cut across, shows grubs within them, where- 

 as in the disease mentioned no grubs will l)e 

 visible. If clubbed specimens are allowed to re- 

 inain m the ground, or if used for pig feeding, &c. 

 in the raw state, and thence passed on to the 

 manure heap, the disease becomes- more virulent 

 and persistent. The disease often occurs on the 



