40 ON NURSERY GROUND, MANURES, ETC. 
nursery ground, particularly during the second year of their 
life, assume a yellow colour in their leaves; and although 
nothing the worse, yet the appearance is often objected to. 
In this case a dressing of guano, followed by rain in August, 
or its application in a liquid state, will change the foliage to 
a darker green in the course of a few weeks. 
It is desirable that nursery ground should be large enough 
to admit of the plots being restored to good condition every 
fourth or fifth year by a well-fertilized green crop of turnips, 
or potatoes, etc. All sorts of two or three year lined plants 
exhaust the ground considerably ; among hardwood, ash, elm, 
and sycamore are the most exhaustive, oak the least so; and 
among the fir tribe, the Norway spruce reduces the condition 
of the ground more than any of the other species. 
Some of the most valuable crops of seedling Scotch pine 
and larch that I have ever seen, were .produced on plots of 
land very much exhausted by nursery crops, but renewed or 
enriched a few months before being sown, by receiving a good 
coating of fresh mould from a field in the vicinity, which dur- 
ing the previous summer had yielded a crop of turnips, which 
had been well manured, and kept clean and free from seeding 
weeds during their growth ; this soil was carted and spread 
on the nursery plots, about two inches deep, and roughly dug 
over during the months of January and February. A mixture 
of various soils is very invigorating for all tree crops; and it 
is found profitable to give an extra quantity of manure to the 
field in exchange for soil well adapted for crops so important, 
particularly where the carriage is not very distant. 
In the private nurseries throughout the country, seedling 
plants are seldom raised, as it is generally found more profit- 
able to purchase young plants one or two years old. These 
we have been in the practice of raising for many years to 
numerous customers both in Scotland and England, who order 
them a year before they are required, whereby we avoid to some 
extent the risk of growing an overstock, and are thus enabled 
to sell them generally about 20 per cent. under the usual rate. 
