If only 50 lbs. of leaf go to each tree, it takes four acres, instead of one, to get the same result.
A great point to be remembered is, that the trees never wear out if properly cared for. Some of the trees first planed in France, nearly 400 years ago, are living still. Neglected trees, however, soon perish.
Now for expenses. Count Dandolo, perhaps still the greatest Italian authority, reckoned that year 5 oz. of graine (eggs), an ounce containing about 40,000, required labour equal to that of one man for 100 days, or 5 men for 20 days. An experienced and careful grower in New South Wales, wishing to make an estimate of his own, did the work for a certain quantity of eggs single-handed for the whole of one season. He reckoned that, if one could do so much, ten men could do at least ten times as much, or more, since in judicious division of labour there is economy; then, calculating the labour at the rate of 7s. a day per man, a very high estimate, he brings the cost to about two-thirds of the gross returns. Now, if an association of women can do this work between them, and they can, the cost of labour goes nearly all into their own pockets.