The subsoil contains also a large quantity of protoxide of iron, a substance frequently found in subsoils containing much organic matter, and to which the air has imperfect access.
The preglacial subsoils were residual clays and sands, composed of the insoluble elements of the country rock of the locality, with some minglings of its soluble parts still undissolved.
The glacial subsoils are made of rocks of many kinds, still undecayed and largely ground to powder.
To these soils and subsoils a large part of the wealth and prosperity of the glaciated regions of our country must be attributed.
It leaches soils and subsoils of their lime and other soluble minerals upon which plants depend for their food.
In some parts the subsoils have been excavated for ballast or gravel, as at Kensington, or for brick earth, as at Highbury, and the pits filled in with rubbish.
As examples of the varying subsoils we may mention the following, in which will be noticed the great depths dug before getting through the made ground: At the Bank of England there were 22 ft.
Müller found the average of a number of analyses of subsoils to be .
This is less on the whole than what has been found in subsoils by Continental investigators.
It has been claimed that alfalfa roots have gone down into congenial subsoils 40 to 50 feet, but usually less, probably, than one-fourth of the distances mentioned would measure the depths to which the roots go.
Usually they penetrate the same to about 2 feet, but in some instances, as when subsoils are open and well stored with accessible food, they go down to the depth of 5 or 6 feet.
It was formerly thought by many that alfalfa would only grow vigorously on soils and subsoils sandy in character, and underlaid at some distance from the surface with water.
Loam soils with reasonably porous subsoils are best adapted to its growth.
It will, however, send its roots down into hard subsoils so deeply that in certain seasons the plants could not be dug up without the aid of a pick.
When they are short, as they must needs be in very stiff subsoils and on thin land underlaid with hard soil, the branches become about as large as the tap roots.
These soils are usually possessed of abundant food supplies to nourish the plants, and the roots can go far down into the subsoils to gather food and moisture.
But good crops of alfalfa may be grown on subsoils so retentive that underdrainage is necessary to facilitate the escape of an excess of moisture with sufficient quickness.
It can be made to succeed on hard clay subsoilsfrom which the surface soil has been removed.
When the subsoils are simply stiff clays, deep subsoiling, as already intimated, may render much service, but when composed of hard pan this may not be practicable.
In all the more porous subsoils in which collars have not been used, the more successful drainers increase the size of the pipes in the minor drains to a minimum size of two inches bore.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "subsoils" in a variety of sentences. We hope that you will now be able to make sentences using this word.
