AMERICAN INSTITUTE. 15T 



ttat it is by study and statement of facts, rather than theoretical discus- 

 eions that we shall arrive at the resolution of the problem, I point out 

 what I have discovered of facts. On many sorts of potatoes, the insects 

 which cause the disease are microscopic — there are four distinct species of 

 the Acarus, of which one only is known, the Oribates casianeus, and one 

 of the Cochineal family, la cockenille en bateau de podurelles, ^'C. On 

 certain parts of fruit, the acarus traces little furrows in lines, sometimes 

 straight and sometimes irregular — very superficial — sometimes these lines 

 are traced from the stem in right lines but short ones. Some apples, for 

 example, the Rat d'Or. It is by night only that the acarus works ; this 

 little insect becomes of a red scai-let color in the fall. In the spring I 

 find it on the young leaves next to the apple and pear buds, but before 

 these bloom it makes reddish spots on the young leaves. It runs extremely 

 quick. The second species has scarce long hair, whitish like its body, is 

 much like mites in old cheese, figs, old wheat, and flour, &c. The third 

 Acarus is almost cylindrical in form ; short, dull white color; its fore feet 

 rose tinted., generally. The largest sort, Oribates castaneus, is dark 

 chesuut-colored, shining ; it resembles a little coleopter, hardly ever seen 

 on apples and pears, except in summer ; it has a keen point on each side 

 of the anterior part of the abdomen. These prick our apricots, making little 

 scabby pustules on them, on the sunny side especially. It is frequently 

 found, at night only, on the pears. Bonne Louise d'Avranches, Doyenne 

 d'Hiver, Beurre d'Amaulis, Saint Germain, &c., particularly where two 

 pears happen to touch. I have many times found it upon potatoes, and in 

 a flat form. I have found it, the white acarus, on truffles, flat and difi"ex"- 

 ent from those I have spoken of. 



A BARREN APPLE TREE. 



Mr. Solon Robinson — Charles B. Davis, of Syracuse wants to know how 

 to make a barren apple tree productive. It is a Baldwin, a foot through, 

 in vigorous health, blossoms full, and fruit set and drops while small. The 

 soil is black clay loam, on clay subsoil. Who will answer this question ? 



I will call upon Andrew S. Fuller, who is a practical grower of trees, 

 having been bred to the nursery business. 



Mr. Fuller — I can only answer that trees in such rich, mucky soil grow 

 wood fast, and make good nursery trees to sell, but not to bear fruit. They 

 are spongy, and the wood is not solid, nor as heavy as trees grown in 

 harder soil. I would dose the land around this tree with lime, salt, ashes 

 and tones, and grow something to make the soil poorer, or change its 

 mucky nature. 



Solon llobinson — In this Syracuse letter above quoted, the following 

 question is asked : Will it pay to apply the mixture of lime, slacked with 

 water saturated with salt, to wheat, oats, barley and grass, grown on clay, 

 clayey loam, or sandy loam — to land somewhat severely cropped, cold and 

 wet. How much to the acre, and where is it best to apply it ? As a gene- 

 ral rule it will not pay to apply anything but draining to land that is " cold 



