Essay on Guano. 431 



ground had not been trenched and highly manured." We 

 quote Mr. Teschemacher's experience : — 



The experiments with guano on trees which have come under my obser- 

 vation, including exotics, number about one hundred and fifty. The action 

 has invariably been to produce large foliage, of a deep healthy green, or 

 with plants, usually covered with a white powder, called glaucous, to in- 

 crease this appearance, and to shorten the joints or intervals from leaf to 

 leaf. This last action, as respects fruit-trees, is of the utmost importance ; 

 every one being aware that long-drawn, long-jointed shoots are the least 

 valuable or productive, and that the fruit-bearing spurs on trees are but 

 branches with shortened joints. Hence the production of short-jointed, 

 stocky branches is the production of so much fruitful wood ; and if, by proper 

 pruning, the sun and air are admitted so as to ripen the wood, a plentiful 

 crop must be the result. 



The best mode of application to fruit trees seems to be, first, to consider 

 where are the young feeding roots — that is, at what distance from the stem, 

 and what depth in the ground, — then to place the guano as near them and 

 as much around them as possible, without being in absolute contact. 



For instance, round an apple-tree often years' standing, dig a trench, one 

 or one and a half foot deep, at about the same distance from the stem that 

 the branches extend ; let this trench be about one foot wide ; then put at 

 the bottom one and a half inch depth of guano, dig it well in, and incorpo- 

 rate it with the soil ; then cover up carefully, and press the earth down. 

 The effect of this application will unquestionably be felt for several years. 



lam rather inclined to attribute this shortening of the joints chiefly to the 

 action of the soluble portions of the guano ; as the pelargonium, the orange, 

 and many other plants which exhibited this appearance, had only been 

 watered with its solution. But, in all applications to fruit-trees, I recom- 

 mend the guano itself, as the insoluble portion contains the chief materials 

 of the seed, to protect and cover which fruit is formed. Where young trees 

 are to be manured, a little guano, dug in at the surface around the tree, as 

 well as in a trench, will be advantageous. 



The use of guano for trees probably combines another advantage of in- 

 estimable value ; this is, the destruction of the insect tribes which are buried 

 in the earth, and emerge from thence with the warmth of spring. The cov- 

 erings of these insects, when they first come out of the ground, are not har- 

 dened ; and, in this tender state, the contact with a moderately strong solution 

 destroys them. I have tried experiments on about eight or ten various cater- 

 pillars, and some other insects have invariably found a solution of guano kill 

 them quickly, except when in an advanced state ; then it took a longer time 

 and a stronger solution. Salt and oil-soap are both apt to be injurious to 

 vegetation ; but, by strewing guano around the trees, and turning it in a little 

 depth, the plant will be benefited, and the insects at the same time destroy- 

 ed. My experiments on this subject, although perfectly convincing and sat- 

 isfactory to myself, have, for want of time, not been conducted with that 

 care and precision which should authorize me to lay them before the public 



