152

SECT. XVI.----EXOTIC TREES AND SHRUBS.

known to thrive in best, we have endeavoured to supply that informa-tion ; which will be understood by applying' to the following

ABBREVIATED CHARACTERS.c. m. read common garden mould.

b. m.1.

b. 1.1. b.

s.

o -s -% -\ -

bog mould.

loam.

bog and loam, the greater part bog.

loam and bog, the greater part loam,

sheltered situation. ^

annual.

biennial.

perennial.

tree or shrub.

As the soils recommended may not be generally understood ; a littleattention to the following rules will enable persons to discover what isfit for their purposes.

Loam —the kihd best adapted to the purpose of growing plants, isof a moderately close texture, between eiay and sand, differing fromthe former in want of tenacity when wet; and not becoming hard whendry; nor is it loose and dusty like the latter; hut in both states pos-sesses somewhat of a saponaceous quality- Jt varies in colour fromyellow to brown, and is commonly found in old pastures: it may alsobe remarked, that where any perennial species of Clover (Trifolium)are found wild, it is almost a certain indication of a fertile loam, andsuch as contains the proper food of plants in abundance.

Bog-Mould —is frequently found on waste lands, where Heaths(Ericee) are produced : it is composed of decayed vegetable matter and"white sand. The best sort is light when dry, of a black colour, andeasily reduced to a powder. Care should be taken to distinguish itfrom Peat, which is hard when dry, destitute in a great measure of thesand, and mostly of a red colour. This contains in great quantitiessulphureous particles and mineral oil, which are known to be highlydestructive to vegetation.

The mould formed from rotten leaves is a good substitute for bog-mould if mixed with sand, and is often made use of for the same pur-poses. These earths should be dug from the surface to the depth of