February 3. 1912 



THE GARDENERS' MAGAZINE. 



95 



THE ERECT^GROWING BIRCH. 



The varietal forms of the Silver Biroh 

 (Betula alba) are many, and of these the 

 majority possess sufficient merit to justify 

 their inclusion in a selection made for beau- 

 tifying ]>leasure grounds that extend over a 

 hirge area, or for the formation of a dis- 

 tinct feature in the park. For compara- 

 tively small gardens, a few of the more 

 distinct Avill suffice; and in making a selec- 



THE SCIENTIFIC INTEREST 



IN SWEET PEAS. 



Mr. T. H. Dipnall's writings are always 

 very interesting to me, therefore I read, 

 two oi three times, his article in vour last 

 issue under the above heading. 



I cannot see very clearly his meaning in 

 the following paragraph: ''Last year it 

 was discovered that if you cross these ex- 



standanl varieties at 

 trouble for ourselves 



all — We introduce 

 We have a few good 



tion for these, as for the larger areas, the eeptional members of a oouphng system, 



and 



varieties should, as a matter of course, be 

 selected with due regard to their adapt- 

 ability for the positions in which they are 



to be planteil. 



Tlie most <lesirable of the varieties for 

 general planting are the Broad-leaved 

 (Betula alba latifolia) ; the Toothed-leaved 

 (B. a. dentata viscosa) ; the Erect-growing 

 (B. a. fastigiata), the Weeping (B. a. pen- 

 dula). Young s Weeping (B. a. pendula 

 Youngi), the Purple^leaved (B, a. pur- 

 purea), and the Xettle-leaved (B. a. urtici- 

 folia). The popular names indicate the dis- 

 tinctive characteristics of the several varie- 

 ties, and serA'e as a very good guide to the 

 plants in making selections for various 

 ])ositions. If a tree of pendulous habit is 

 required, the planter has the choice be- 

 tween the ordinary weeping variety 

 Young's AVeeping, and as these differ much 

 in habit, the planter should take advan- 

 tage of any opportunity he may have for 

 seeing trees of the two forms ; but those 

 who have no such opportunity, and require 

 the tree or trees for a small garden^ should 

 .select Young's variety. In large pleasure 

 grounds^ both weeping varieties might with 

 advantage have a place. If it is desired 

 to produce a contrast to one of the several 

 irolrlen-leaved trees the purple-leaved must 

 'je selected, and if a tree of erect growth 

 would be the most appropriate for a given 

 ]>o>itioii, the fastigiate form of which an 

 illustration is given herewith, will be found 

 of much value. 



of the Silver 

 occupies much the same position 

 among the birches as that occupied by the 

 Lomliardy poplar among the species - of 

 l opulus, and consequently is well able to 

 render good service as a component, part 

 ^^f garden scenery. It is not suggested that 

 ^ IS superior to either the typical Silver 

 .^irch or any one of its varietal forms ; but 

 It IS remarkable for its light and elegant 

 ^»^pect. and for the distinct and charming 

 ^^rtect It produces, whether growing singly 

 ^"iiong its near relatives, as in the case of 

 tlic specmien herewith illustrated, or ar- 

 i<inn;p(i m groups in spacious pleasure 



.s or park lands. The tree is 

 i(^\v, rare, or expensive, and consequentlv 

 ore IS no obstacle to it being utili,s<Hl in 



'onr'''^^" distinct feature in the 



' »^^*^v of park or garden. 



waved varieties which are good seeders, 

 notably Mrs. Hugh Dickson, which seeds 

 as well as any plain standard variety ever 

 did. My idea would be to utilise such a 

 one for crossing to breed for free-seeding 

 qualities. 



May I point out to Mr. Dipnall something 

 which he might think about wlien p<mde)'- 

 ing over the problem of burning or seald- 

 ing.^ King Edward Spencer never burns, 

 you reverse the system in their progeny^ never goes dingy purple under glass, and I 



The 



Birch 



last-named 



variety 

 much the 



cr 



i"'nindj 



not 



G. 



mrdouble Zonal 

 w Chavarri Herm 



P*r,„„i „ belong. toTh„r:So"° growin, 



^^oil;:";, t''^^' of i>ur French nei^^h- 



^ours of .Jr French nei 



^^^- iA^ Denmark is one . 



oest known ^v.^.i.„ Chavarri Her 



of 



^Vhen irown ^ h'''''^ ^ ^^^^^ ^^^^^^^^ ti^*- 

 '^''''^^Ah7liZv%^'''^'^ it flowers well 



^^^^^'^t^he^Z^^^^^^ plants 



^vhirh '^""^^ctive of them. Tlie 

 "eo.\a ver.^rrt°^'^t^ lanceolate in shape 

 !"^>^lar shaped bt^'""° the scarlet 



'"■-u^hout ^the \lZ "^t ««nti„ue to develop 

 ^' fl^'Mors best wt„ .'^.^"T ^'^^ «prin^. 

 l^^'-^^d to light and ^ P^^»t« ^^11 <^x- 

 I'^^'t of UrLlZ,''l^---S^out the latter 



BETULA ALBA FASTIGIATA. 

 An eleo-ant variety of the White Birch of upright growth at Kew. 



could name man/ others whkli do not. 

 rnderneatli that fact lies tlie same analogy 

 standard ai'id an extra fertile wavy 'pea, as Mr. Dipnall thinks he has discovered out 



so that if in your seedlings of the seeond 

 szeneration vou find an extra sterile plain 



and cr{)ss these two, you obtain ^ race in 

 which the great majority of the waved peas 

 will l3e extra fertile and the plain stan- 

 dards sterile/' 



That may be so. Ha^ it been proved? 

 Brieilv, I think Mr. Dipnall means tnat in 

 the F2 we will get var:eties with wave<l 

 standaiTls -which wil' be good seeders, but 

 it seems to me we take a retnigrade step 

 to obtain this bv crossing with the plain 



of doors. 

 Edinburgh. 



CuTUnERTSON. 



CHRYSANTHEMUMS AND HOW TO GROW 

 THEM FOR EXHIBITION," by J. B. Wroe.-Full 

 details on timing and stopping for Northern, 

 Southern, and Midland ^rowera, selections of th*^ 

 best varieties, illustrated inistructions on taking the 

 buds, cuttings, staging, etc. Pricee Is. net. by post 

 Is 2d.; cloth, le. Gd.. by post Is. 8d., from W. H. 

 and L. Collingridge. 148 and 149, Aldensgate Street. 



l^ndon. 



