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Show HOME COURSE IN SCIENTIFIC AGRICULTURE FIFTEENTH ARTICLE. THE PROPAGATION OF PLANTS. By L. C. CuROETT, Horticulturist, Bureau Bu-reau of Plant Industry, United States Department ot - Agriculture. IN addition to using tuo natural moans of reproduction of plants by seeds, bttlbs, etc., mail haa developed de-veloped several urUllclul wnyu, of whlcu-tlio principal nro cuttings, layering, layer-ing, grafting and budding. A cutting Is n detached portion of a plant inserted in soil or in water for tho purposo of producing n uey plant. This method of propagation Is considered consider-ed most important. Tho most common form of hardwood cuttigs consist h of a straight portion of a shoot or cane nearly uuiform in sfzo throughout and containing two or moro buds. At tho lower end- It is usually cut off Just below be-low n bud, becauso roots develop most readily from tho Joints. At tho top tt is usually cut off somo dlstnnco nbovo tho highest bud. A heel cutUng fon-slsts fon-slsts of,tho lower portion of n branch, containing two or moro buds, cut off in such n manner ns to carry with it a small portion of thnt branch forming tho so called "heel." A mallet cutUng is produced by severing tho parent branch nbovo and below a shoot, ho as to lenvo a section of it on tho basoof tho cutting. Tho principal advantage '&&?$ yM l . i Photo by Long- Island agricultural experiment experi-ment station. DWAItF BARTLETT VTJlH anOWN ON QCDJCH STOCK. In tho use of heel and mallet cuttings lies in tho greater certainty of doyol-oping doyol-oping roots. Tho principal drawback is that only ono cutting can bo mado from each lateral branch. When it is desired to make the largest lar-gest number of cutUngs from a limited limit-ed supply of stock, cuttings -aro mado containing but ono bud each. Such cuttings nro commonly started uuder glass with bottom heat cither In green-houso green-houso or hotbed. Cuttings aro usually mado with two or moro buds. Tho cuttings nro mndo whllo tho wood is dormant durlug tho fall or early winter. As fast as mado they aro tied In bundles of twenty-flvo or fifty (butts nil ono way) and burled bottom end up in n trench and covered to a depth of two or threo Inches with sand or mellow soli. Cuttings may also be kept over winter in n cool -cellar burled in sand, sawdust or moss. The following sprlug cuttings nro set about threo Inches apart In a trench with only tho topmost bud or buds nbovo tho surface. Tho soil Is then replaced In tho trench and thoroughly packed. Iu planting, the cuttings should be exposed to light and air as little us possible. After being planted tho cutting should develop roots und put forth leaves, and by tho noxt fall or spring It should bo ready to put out. Ilorbuceous or soft wood cutting!" nro exemplified In tho "slips" usrd to iucreaso tho numbers of houso plants. This method of propagation can bo employed In tho wlntor tlmo under glass. Herbaceous cuttings may bo mndo from tho leaf or stem. Leaf cuttings are commonly employed employ-ed in multiplying plnnts having thick, fleshy lenves contnlnlug n large quantity quan-tity of plnut food either In the body of tho leaf or Its larger ribs. As i general rule, In preparing slips tho leaf urea should, bo reduced to u minimum In order to lesseii evaporation. Usually an Inch of broken stouo or coarso gravel overlaid with ono and ono-half to threo Inches of sand will be .found amplo for all soft wood cuttings. cut-tings. ' Short cuttings of tho roots muy bv used In tho p-opagatlpn of tunny plants, especially those w.blch show u natural tondency to sucker. ' A layor Is a branch so placed In contact with tho enrth as to Induco It to throw out roots mid shoots. Layering Lay-ering frequently proves a satisfactory method with woody plants which do not roadlly take root from cuttings. All tho common pomuceous fruits, tho Btooo fruits and tho cltrun fruits nro now multiplied by grafting or bud-ding. bud-ding. A Bclon is n portion cut from i plant to be inserted upon another tofl tho same) plant, with, tho lutontlou that' it shall KToyr. Except for herbaccoui grafting the wood for scions should W taken whllo In a dormant or resting condiUon. The tlmo usually considered consider-ed best Is after the loaves have fallen, but beforo severe freezing begin). Tho scions are tied in bunched and buried In moist sand, whore they will not freeze nnd yot will be kept cold enough to prevent growth. Good results re-sults often follow cutting scions In tho spring Just bofore or at tho tlmo the grafting Is to bo dono. If cloft graft-lug graft-lug is tho stylo to bo employed this prncUco frequently gives good results, but spring cuttlug of scions for whip grafting is not desirable. Tho stock Is tho plant or pnrt of a plant upou which or Into which tho bud or scion is Inserted, For beat results re-sults In grafting It is essential thnt tho stock bo In nu active condition. Cloft graftiug is particularly adapted to largo trees whon for any reason It becomes necessary to chango tho variety. va-riety. Branches too largo to bo worked work-ed by other methods can bo cleft graft-od. graft-od. A branch ouo or ono and one-hnlf Inches in diameter Is severed with a saw. Caro should bo taken that the bark bo not loosened from uuy portion of tho stub. Split tho exposed end with n broad thin chisel or grafting tool. Then with n wedgo or tho wedgo shaped prong at tho imhI of tho grafting tool spread tho cleft so that tho scions may bo inserted. Tho sclou should consist of a portion of tho previous senson's growth and should bo long enough to havo two or threo buds. Tho lower end of the scion which Is to be Inserted into the cleft should be cut Into tho shape of a wedgo, having tho ouer edgo thicker thnn tho other. In general It Is a good plan to cut tho scion so that tho lowest bud will come Just ut tho top of this wedgo, so thnt It will be near tho top of tho stock. To make this contact of tho growing portions doubly certain tho scion is often set at a slight nngle with tho stock into which It is Inserted. After tho scions havo been set the operation of cloft grafting Is completed by covering all cut surfaces with a layer of grafting wax. Whip grafting Is almost universally used In root grafting. Ithns tho advantage ad-vantage of being well adapted to small plants only ouo or two ycurB of ago, and It can bo done indoors during the comparative lelsuro of winter. Tho graft Is mado by cutting tho stock off diagonally one long smooth cut with a sharp knlfor leaving about three-fourths of an Inch of cut surface. Placo the knife about ono-tklrd of the distance from tho end of tho cut surface sur-face at right angles to the cut and split tho stock In tho direction of Its long axis. Out tho lower end of tho scion ln like manner, and. Trben the two parta aro forced together tho" surfaces will fit nently togother, and l, ono will nearly coyer the other If scion nnd stock aro of tho name size. A difference dif-ference may be disregarded unless it bo too great. After tho scion and stock hnvo been locked together thoy sbjpuld be w,rnpped with flvo or six turns of waxed dotton to hold tho parts fiamly together. It is in root grafting thatl tho ' whip graft finds Its dlstluctlvo OclAl Tho roots nro dug and tho scions We cut in tho fall nnd stored. Tho v rork of grafting may bo dono during ,tho winter months. When tho opera Uon has been performed tho grafts aro packed away in moss, sawdust or ind in a cool cellar to remain until spt ing. In ordinary propagation by mean a of whip grafts tho scion is cut with nl ut threo buds, and tho stock Is nearly,' us long nH tho scion. Tho graft isj bo planted ns to bring tho union of stjock and scion not very far below the i ur-faco ur-faco of tho ground. But where tho trees uro required to bo cspech illy hardy In order to stand sovere wlnt era and tho roots used uro not known1 to bo so hardy as tho plants from wh Ich tho scions havo been cut a dlffor ent plan Is udoptcd. Tho scions nro 5ut much longer, and the roots may bo mt shorter, and the graft 1b planted so deep ns to causo roots to issuo fr am tho lower ond of tho scion. Whon ti ak-en ak-en up to bo set in tho orchard tho olrlg-lnnl olrlg-lnnl root may bo removed entirely.! Budding Is ouo of tho most cconpm-fcnl cconpm-fcnl forms of artificial reproduction, and each year witnesses Its niorcJ gen-oral gen-oral use. j Tho operation of budding Is njimple and can bo dono with great spewed by export budders. Tho work has usually to bo dono In July, August or early Septombor. Tho bud should bo ikcn from wood of tho presont season's growth. Since tho work of buddnpg Is dono during tho season of a'.ttlvo growth tho bud sticks aro prcpurejjl so that tho potlplo or stem of each lortjf Is left attached to servo as a haudl' to aid In pushing tho bud homo wheili lu-sorting lu-sorting It beneath tho bark of B tho stock. This Is what is usually ciftlled a shield bud and Is cut so that a slinall portion of tho woody tlssuo of I, tho branch Is removed with tho bud. 11 Tho stock for budding should blf at least as thick ns tho ordinary load pencil. pen-cil. The height at which buds urW Inserted In-serted varies; tho nearer tho groutiJ! tin, better. When the bud Is mado a llgJiture is then tightly drawn about, nhovif und below tho bud to hold it in plne' until un-til n union shall bo formed. Bauiws of raflla about eight or ton inches llong tnako a most convenient tying uimto-rlat uimto-rlat As soon as the buds havo united with tho stock the lignturo shouiH b cut In order to prevent glrdlluelgthe stock. This dono, tho oporntlon isif complete com-plete until tho following spring, Bwhon All tho trees In which tho budsabave "taken" should havo the top cat off just nbovo tho bud. 1 'J ho ouo objection to budding lij that It causes an unsightly crook liT the Ijody oftlift tree unless the tfe ta planted (loop lu the orchard. 1 iL P |