1(586

ARBORETUM AND FRUTICETUM.

FART III.

surface of the soil. Du Hamel obtained abundance of plants by strewing soilover the surface of the ground under a seed-bearing alder, tree in autumn, afterthe seed had dropped. When the seed is sown in autumn, the plants willcome up the following spring; and, when it is sown in spring, they will gene-rally come up in the course of five or six weeks after sowing. Spring sowingsshould be made much thicker than autumnal sowings; because many of theseeds, unless they have been very carefully excluded from the air, lose theirvital power during winter. The plants from spring-sown seeds will attain theheight of from 3 in. to 6 in. the first summer. The second year they will bedouble or treble that height; and in three or four years, if properly treated, theywill be 5 ft. or 6 ft. high. The nursery culture and after-management inplantations have nothing peculiar in them; except that, when full-growntrees are to be cut down, it is advisable to disbafk them a year before; apractice as old as the time of Evelyn. When alders are cut down as coppice-wood, in spring, when the sap is in motion, care should be taken that the cutsare not made later than March; and that they are in a sloping direction upwards.If, at this season, the cuts are made downwards, the section which remainson the stool will be so far fractured as, by the exudation of the sap, and theadmission of the weather, no longer to throw up vigorous shoots, and it willdecay in a few years.

Accidents, Insects, and Diseases. The alder is liable to few accidents fromhigh winds : but the Adimonia alni Fab. deposits its eggs on the young buds ;and the larvas are frequently so abundant, as to consume the leaves almostentirely. There is also a small worm, the caterpillar of some coleopterousinsect, which penetrates through the bark into the wood, and ultimatelydestroys the trees. (Diet, des Faux, &c.) This is probably the Callidiumalni Fab., one of the longicorn beetles. A small species of jumping weevil(Orchestes alni Leach ) also attacks the leaves, as well as Phyllobius alni Fab.,belonging to the same family, and Galeruca lineola Fab. (the Chrysomelagrisea alni, fem., of De Geer). Amongst lepidopterous insects, Cerura vinula,Pygas'ra bucephala, Notoddnta dromedarius, Lophopteryx camelina, Orgyiaantiqua, Zeuzera as'seuli, Porthesia chrysorrhoe'a, all belonging to the Linnaean.Bombyces; Apatela /eporina, Acronycta alni and psi (or dagger moths),belonging to the iVoetuidas ; Geometra ulmaria, Drepana falcataria, and se-veral T’ortricidse and 7'ineidm, feed, in the larva state, upon the alder. Someof these being, however, general feeders, are not so injurious as the others.

Statistics. Recorded Trees. The finest alder trees which Mitchell ever saw were probably thesame as those alluded toby Gilpin (p.1682.), in the Bishop of Durham’spark, at Bishop-Auckland, wherea tree, in 1818, had a trunk which measured 11 ft. in circumference. It grew upon a knoll on aswamp. The finest alder poles the same author ever ob-served were in Arnold’s Vale, below Sheffield Place, Sussex:in 1815, these were from 60 ft. to 70 ft. high. The alders onthe banks of the river Findhorn have been already men-tioned.

Existing Trees. In England, in the environs of London,at Ham House, Essex, A. g. emargin&.ta is 15 ft. high, thediameter of the trunk 2 ft. 4in., and of the bead 28 ft.; atSyon, A.g. lacinikta {fio. 1542.) is 68 ft. high, the diameter ofthe trunk 3 ft., and of the head 63 ft.; at Kenwood, Hamp-stead, 60 years planted, the species is 60 ft. high, the diameterof the trunk 2 ft. 10 in., and of the head 60 ft. In Devon-shire, at Killerton, it is 56 ft. high, with a trunk 3 ft. 3 in.in diameter: in Dorsetshire, at Melbury Park, 100 yearsplanted, the species is 50 ft. high, the diameter of the trunk3 ft., and of the head 46 ft.; and A.g. lacinikta is 50 ft. high:in Somersetshire, at Nettlecombe, the species is 35 ft. high ,the diameter of the trunk 2 ft. 10 in.,and of the head 32 ft.;in Surrey, at Farnham Castle, 50 years planted, it is 50ft.high; at Woburn Farm, A.g. laciniata is 70 ft. high, diameter of the trunk 4 ft., and of the head65 ft. ; in Sussex, at Westdean, A. g. lacinikta, 12 years planted, is 32 ft. high ; in Berkshire, at BearWood, 12 years planted, the species is 40 ft. high.; in Buckinghamshire, at Temple House, 40 yearsplanted, it is 50 ft. high ; in Cambridgeshire, in the Cambridge Botanic Garden, it is 50 ft. high,the diameter of the trunk 2 ft. 5 in., and of the head 36 ft; in Denbighshire, at Llanbede Hall, it is54 ft. high, the diameter of the trunk 3 ft., and of the head 34 ft.; in Herefordshire, at EastnorCastle, 18 years planted, it is 60 ft. high : in Hertfordshire, at Cheshunt, 8 years planted, it is30 ft. high ; and 10 years planted, it is 20 ft. high ; in Lancashire, at Latham House, 50 years planted,it is 58 ft. high, the diametei of the trunk 3 ft., and of the head 52 ft.; A. g. lacini&ta, 20 yearsplanted, is 36 ft. high : in Leicestershire, at Elvaston Castle, the species is 89 ft. high, with a trunk2 ft. 7 iti. in diameter ; at Doddington Park, 35 years planted, it is 41 ft. high : in Monmouthshire,at Dowlais House, 12 years planted, it is 35 ft. high; in Northamptonshire, at Wakefield Lodge,