IRISH GARDENING 



149 



section to last a year, will thus last four years 

 on the original bark, by which time the first 

 section will have renewed its bark and be ready 

 to work again. 



Special knives are used for tapping. The one 

 used in making the first cut has a three-sided 

 cutting edge which completely removes a piece 

 of bark, leaving a narrow channel extending 

 almost to the cambium layer of the wood. In 

 subsecpient tapping a different tool is used — 

 one having but two cutting edges, and known 

 as a paring knife. 



The lower edge of the opening cut is the 

 part tapped. A very thin slice of the bark is 

 cut away which re-opens the wound and causes 

 the latex to flow. This operation is repeated 

 every alternate day, a tree thus being tapped 

 about 150 times a year. The latex flows down 

 the oblique cuts and gathers at the point of 

 the V, at which place a piece of tin is inserted 

 to guide it into a cup which is placed underneath. 



A remarkable feature of the rubber tree is 

 its response to wounding. A new tree on first 

 being tapped gives no flow of latex, but regular 

 tapping induces a flow which increases each 

 time, until at about a month from starting the 

 tree is giving its maximum. 



It will be gathered that this continual paring 

 of the lower surface of the cut means in time a 

 large removal of bark. The latex vessels are 

 situated in the inner layer of bark next the 

 cambium, and tapping has to be down to the 

 cambium to get the latex, but not into it, or the 

 tree is injured. The wounding is always thus 

 being carried farther down the tree, and healing 

 should be following up close behind it. The 

 removal of bark must not be at so rapid a rate 

 that healing cannot keep pace with it. The 

 division of the tree into sections is to ensure 

 the bark lasting a given number of years. 

 Fortunately, the removal of a very thin shaving 

 of bark is sufficient to open the wound, and it 

 results in as much latex as a thick shaving. 



As the tree gets bigger other V cuts are put 

 above, and they are then joined together by a 

 vertical channel running through the points. 

 A system of several V's joined together is known 

 as a '" herring bone " system. 

 ( To be continued.) 



£r> $£?* $2^* 



The Educational Company, Dublin, have in 

 the press a book dealing with the subject of 

 planting and growing of the various crops which 

 may be profitably grown in Uganda. The author, 

 Mr. E. Brown, F.L.S., has a long experience in 

 the country, and was formerly Assistant Director 

 of the Forestry Department at Entebbe, Uganda, 

 and is now manager of the Kivuvu Rubber 

 Company, so is well qualified to deal with this 

 subject. — Ed. 



Shrubs for Forcing. 



So accustomed are we to bulbs of various kinds 

 for use in providing a spring display indoors 

 that we are apt to overlook many kinds of 

 woody subjects of equal beauty and utility. 

 A few shrubs, such as Azaleas, Deutzias, and 

 occasionally Lilacs, are certainly in fairly 

 common use, but still there is a host of hardy 

 outdoor shrubs which flower naturally in the 

 spring months which, with very little trouble, 

 can be induced to flower in the warm greenhouse 

 while outside conditions are still the reverse of 

 spring-like. 



All early spring flowering trees and shrubs 

 flower on spurs or shoots which have been made 

 and matured the previous summer and autumn. 

 All they have to do then is to wait for the 

 genial showers and rising temperature of spring. 

 These conditions have to be produced artificially 

 when it is desired to force our shrubs into 

 flower before their natural time. Consequently 

 it is necessary to bring them indoor?, and the 

 best way to do this is to have the shrubs petted 

 or put in tubs or suitable pots the previous 

 autumn. Then they may be plunged in reserve 

 quarters and brought in as required. It is well 

 to use a good compost, such as would be used 

 for fruit trees, in pots, and with ordinary 

 cultural care, such as an annual top-iressing and 

 careful watering, some subjects may be forced 

 for several years ere they require repotting or 

 planting out again. Needless to say it \? 

 unwise to submit them to too much heat when 

 first brought in. The temperature of a vinery 

 which is being started in January would provide 

 ideal conditions at first, while in a few weeks, 

 when the buds are beginning to burst, a higher 

 temperature soon brings them into flower. This 

 would follow naturally in the vinery, but it is 

 just at this stage they should be moved to the 

 greenhouse or conservatory, where the genial 

 atmosphere maintained for bulbs, &c, will suit 

 the shrubs admirably. Later in the spring 

 progress is more rapid, and it is difficult to keep 

 back the earliest flowering kinds, so that a cool 

 house shut up early to retain the sun-heat will 

 be sufficient to stimulate the flower buds into 

 action. It is important that too much heat be 

 not applied at first or many of the flower buds 

 wi'l fail to open and young growths will appear 

 instead. Gentle syringing with tepid water has 

 a beneficial effect, but this may be discontinued 

 while the shrubs are in flower. The earliest 

 subjects which flower on shoots of the previous 

 year must be pruned hard back when the 

 flowers are over, otherwise they will soon get 

 too large. They must then be returned to a 

 house, from which frost can be excluded, to make 



