210 PRACTICAL PLANT PROPAGATION 



QUERGUS Continued 



There is a great call in foreign countries for our White Oak; but be- 

 tween the difficulty of shipping acorns of it in good condition and the 

 embargo placed on plants from this country, the demand cannot be 

 met at all. This, the White Oak, is the most valuable of all our Oaks 

 for timber purposes, although others are valuable and all serve a good 

 purpose for fuel. 



CUTTINGS. The evergreen species may be increased by this method. 



GRAFTING. Q. Robur var. fastigiata is grafted on Q. Robur, the 

 English Oak, in Winter; on potted plants or on outdoor plants in 

 Spring. In grafting the Oaks choose allied species for stocks. 



INARCHING. Varieties inarched on type. 



QUINCE. (See Cydonia.) 



RAPHIOLEPIS. Indian Hawthorn. 



CUTTINGS. Ripe wood under glass late in Summer. 

 GRAFTING. Used on Cratsegus. 



RASPBERRY. (See Rubus.) 



RETINISPORA. (Often spelled Retinospora.) 



CUTTINGS. A rapid method, taken in early Winter, placed in green- 

 house with a little bottom heat. (See fig. 21.) 



Juvenile forms of these Retinisporas are said to be produced by 

 propagating from seedlings and continuing to propagate from the 

 slower growing branches. 



GRAFTING. Marinus Van Cleef, in The Florists' Exchange, writ <? s 



"Retinisporas and Thuyas are propagated practically the same way 



as the Juniper; only they do not require as much care (see Juniperus 



p. 198), being among the easiest plants to propagate. Excellent success 



can also be had by the following methods: 



Dig up the young wild stock late in the Fall, and heel the plants in a 

 place where the frost cannot touch them, so that when the process of 

 propagating begins in March, they can easily be taken out of the trench. 

 The cions used can be as big as you can get them, and when grafted, 

 they can be placed in the greenhouse very close together. Potting 

 them first is not essential if the work is done this way, and by not doing 

 it you save a lot of trouble and time." 



RHAMNUS. Common Buckthorn. 

 *SEEDS. Stratify in Autumn. 

 CUTTINGS. Hard wood. 

 GRAFTING. Some of rarer sorts are grafted on R. cathartica. 



RHODODENDRON. 



SEEDS. The seed is very fine and frequently, falling beneath the old 

 plants, will grow nicely. In the greenhouse they may be sown from 

 January to March in a soil consisting of sand, peat and a little 

 loam. Do not cover, except with a layer of sphagnum, and place a 

 pane of glass over the pots. Immediately upon germination the 

 glass must be removed. R. ponticum when used as a stock is 

 raised from seed collected when ripe and hung in a boiler room 

 to dry thoroughly. Crush seed pods with a hammer and sift to get 

 all of the seeds. When the seedlings are up sift some fine sand 

 among them to prevent damping-off. Can be wintered in frames 



Srotected hi cold weather and aired on warm days. Transplant 

 i June. Trim plants to a single stem. 



