394 



STATE BOARD OF AGRICULTURE. 



Xo. 29.— Big Rapids, Mecosta Co. 



Sec. 22, T. 15N.. R.10 W. 



Selected by G. W. Warroii. 



Timber: beech, maple, Ij-nn. etc. 



Sand and Silica - 76.00 



Alum ina 10.00 



Oxide of Iron 3.41 



Lime - 1 .14 



Magnesia 49 



Potash 1.80 



Soda 1.16 



Sulphuric Acid 24 



Phosphoric Acid 33 



Organic matter containing 



.10 Nitrogen 3.18 



"Water - 1.90 



Total Asli-food 5.16 



Capacity for water 43,80 



Xo. 30.— Sherman, Wexford Co. 



Sec. 10, T. 23 N., R. 12 W. 



Selected by IT. D. Griswold. 



Timber: maple, roclc elm, lynn, beech, 

 and a little hemlock. 



Sand and Silica 86.74 



Alumina 4.32 



Oxide of Iron 2.10 



Lime 65 



Magnesia 24 



Potash 83 



Soda 34 



Sulphuric Acid 14 



Phosphoric Acid .15 



Organic matter containing 



.11 Nitrogen 3.26 



Water 86 



Total Ash-food 2.35 



Capacity for water 44.00 



No. 31. — Elk Rapids, Antrim Co. 



Sec. 33, T. 29 N., R. 9 W. 



Selected by Geo. E. Steele. 



Timber: maple, lynn, elm, some hem- 

 lock and beech. 



Sand and Silica 84.68 



Alumina 4.82 



Oxide of Iron... 3.20 



Lime 95 



Magnesia 36 



Potash .98 



Soda .40 



Sulpliuric Acid 16 



Phosphoric Acid IS 



Organic matter containing 



.08 Nitrogen 3.14 



Water 65 



Total Ash-food 3.03 



Capacity for water 52.10 



For the sake of comparison, the capaci- 

 ty for water (or the percentage of water 

 the dry soil will hold), of the following 

 soils, is introduced: 



"Pine barrens" of New Jersey 25.60 



"The plains," Baldwin 29.20 



" " Walton Junction 30.40 



" " Kalkaska 33.10 



To any not familiar with agricultural chemistry such tables will appear very 

 dry and uninteresting, or even unintelligible. I will try to give you some insight 

 into their meaning. Looking at these tables you see that "sand and silica,'' 

 ''alumina" and "oxide of iron" make much the largest part of each soil. 

 You are all familiar with sand. Silica and alumina, when chemically com- 

 bined, form clay. Oxide of iron is the material which gives the reddish or 

 brownish color to most soils. The great bulk of nearly all soils is made up of 

 sand, clay and oxide of iron. Alumina is never found in the ash of cultivated 

 plants ; a certain amount of silica and oxide of iron is found in the ash of all 

 plants; but the great mass of these materials, as found in the soil, is of no 

 Avorth in the chemistry of plant life ; they are the mechanical agents of the soil, 

 and are of worth mainly from their relations to temperature and moisture and 

 by giving mechanical support to the plants. Their chief office in the soil is 

 physical, and not chemical. They render the soil light or heavy, porous or 

 retentive. The organic matter of soils, besides furnishing a supply of com- 

 bined nitrogen, is chiefly valuable for its physical relations to temperature, 

 moisture and porosity of soils. 



Leaving out of account the mechanical agents of the soil, which mainly in- 

 llucuco the physical conditions of soils, there remain lime, magnesia, potash, 

 soda, the sulphates and phosphates. While these substances make up the 

 smaller part of all soils, they make uj) tlic larger part of the asli of all culti- 

 vated plants. They are necessary conditions of ])lant growth; in their absence 

 no plant can grow ; when they are present in very limited amount plant growth 



