Finding or making enough well-finished compost to cover the garden several inches deep (what it takes to lift humus levels to 10 percent) is enough of a job.
Humus is a spongy substance capable of holding several times more available moisture than clay.
The higher the humus level gets, the more rapidly organic matter tends to decay.
Though incorporation of extraordinarily large quantities of organic matter can turn the top few inches into something that behaves a little like loam, it is quite impractical to work in humus to a depth of 4 or 5 feet.
A massive humus amendment would increase that to 3 1/2 inches in the top foot or two, relatively not as much benefit as in sandy soil.
Humus can improve many aspects of soil but will not reduce a garden's overall need for irrigation, because it is simply not practical to maintain sufficient humus deeply enough.
Therefore, the more humus that can be plowed into the soil, other conditions being equal, the greater is the ability of the plants growing in that soil to withstand drouth.
As soils are cultivated, the tendency is for the humus to become "burned out" and to have a reduced moisture-holding capacity.
Don't try to produce crops without maintaining the humus supply in the soil.
In such cases the application of lime, increasing the humus content, and deeper plowing will be found helpful.
Aside from the supplying of water by irrigation, a rather costly process under most conditions, the water resources of most soils can be greatly increased by adding to their humus content.
Incidentally, the incorporation of large quantities of humus in the soil creates a condition of acidity which may call for the application of lime as a corrective.
Humus serves as a source of acid-generating material which further breaks down soil particles and, most important of all, serves as a food for millions of microscopic plants which develop and die quite beyond the scope of human vision.
This is when it is growing in moist loam, upon which rain or floods have washed down good layers of humus from woods at a higher elevation.
The modus operandi of burning peat is very simple; it acts by diminishing the superabundant quantity of humus or other organic matters, which, in the previous section we have seen to be so injurious to the fertility of the soil.
The particular phenomena of vegetation also afford abundant evidence that humus cannot be the only source of carbon.
On the other hand, our daily experience affords innumerable examples of plants growing luxuriantly in soils and places where no humus exists.
But though the parts then stated lead to the inference that, as a direct source of these substances, humus is unimportant, it has other functions to perform which render it an essential constituent of all fertile soils.
But Saussure has gone further, and shown that even when present, humus is not absorbed.
It is obvious from these and many other analogous facts that humus cannot be the only or even a considerable source of the carbon of plants, although it is still contended by some chemists that it may be absorbed to a small extent.
The earlier chemists and vegetable physiologists attributed to the humusof the soil a much more important function than it is now believed to possess.
The humus introduced by the liberal applications of manure has made it black.
The soil for palms need not contain as much humus (leaf-mould or peat) as that for most other house plants.
Fill in with at least four inches--better six--of good garden soil containing plenty of humus so that it may allow water to soak through readily.
When this humus is once exhausted there is no way to repair the damage but to wait for the slow rock-decay.
When that was written the world had no proper tillage tools and the importance of humus was not even dreamed of.
Unless we pay special attention to thehumus content of the soil we are likely to use lime to dissolve out plant foods that are not needed by the present crop, and, therefore, cannot be utilized.
The ease with which soils absorb, retain or lose moisture, depends mostly on their texture, humus content, physical condition, and surface slope or artificial drainage.
American plow makers also have recognized the necessity of mixing humus with soil in the act of plowing.
He pointed out, further, that the comparative insolubility of humus in water, or even in alkaline solutions, told against its acceptance as correct.
The old theory, therefore, that the presence of humus in a soil is a condition of fertility, is not so far removed from the truth.
Despite, however, the experiments of Saussure, Braconnot, and Sprengel, the belief that plants derived the carbonaceous portion of their substance from humus still seemed to be commonly held in 1840.
While Liebig, therefore, can scarcely be said to have been the first to controvert the humus theory, he certainly dealt it its death-blow.
Thaer held that humus was the source of plant-food.
Where there is an abundance of humus in the soil there is likely also to be an abundance of nitrogen.
The most elaborate investigation of the composition of humus has been carried out by Mulder.
Of these, sand possesses this power to the least extent, clay to a greater extent, while humus possesses it most of all.
One of the most striking of the arguments he brought forward was the fact that the humus of the soil itself consisted of the decayed vegetable matter of preceding plants.
The humus theory seems to have been first promulgated by Einhof and Thaer towards the close of last century.
Besides this loss of nitrogen encountered in the burning of the trash, the organic matter which would later form humusis completely destroyed.
The place selected for seedbed and nursery should be well drained, with a loamy soil, the richer in humus the better.
Local tracts of naturally unforested land are rarely planted, chiefly because the absence of shade has allowed the sun to burn out the limited humus supply and to prevent more from accumulating.
It is the same on the playas along the river; the recent additions to the flood plain are easy to cultivate, but they lack humus and a fine matrix which retains moisture and prevents drought or at least physiologic dryness.
When it was complete we found that we had penetrated to the under-layer of humus which told us that we had come to the rotted bottom of the chest in which the treasure had been buried.
It was almost as fine as flour, and quite as white, but upon closer inspection I saw that it was flecked in spots with bits of black humus--humus like that formed by well-rotted wood.
There is no twilight to speak of in the tropics, and the sunset glow was fading rapidly, but there was still light enough to show the place in the pit bottom where the bits of black humus were thickest.
It seems to live, not upon the sap of these trees, but upon the dead roots and decayed wood, a specially prepared humus without which it may not thrive, even in its own limited, elusive way.
I have seen the sun do it every June in countless gardens where, out of this same humus and soft rains, his potency works the transmutation as if in a night.
This increases the humus which the soil needs and imparts all the desirable characters and qualities which humus carries.
It would be worth more on a heavy soil, because the danger of drying out would be less and the surety of reduction to humus greater.
But grape pomace, after going through fermentation and in the process of decay, makes humus in addition to giving potash and other desirable substances to the soil.
Straw, by its decay in the soil, produces humus and, therefore acts in the same way just as does the decay of other forms of vegetation.
Stable manure alone will restore the humus and overcome the rebellious behavior of the soil.
It is probable that the reduction of humus is due more to the lack of effort to maintain the supply than to the actual destruction of it by culture methods.
Even where this is not done, the alfalfa will add to the humus of the soil by its own wastes both from root and stem.
Any fresh excavation of cellar or cistern, or cut for road or railway, will show the characteristics of the humus layer.
On the preglacial hillsides the humus layer must have been comparatively thin, while the broad glacial plains have gathered deep black soils, rich in carbon and nitrogen taken from the atmosphere.
As it sinks into the ground and becomes what is termed ground water, it takes into solution from the soil humus acids and carbon dioxide, both of which are constantly being generated there by the decay of organic matter.
Soil usually contains more or less dark, carbonaceous, decaying organic matter, called humus, and is then often termed the humus layer.
If the soil is infertile, some form of humusshould be worked in at the time of planting.
Cultivation, with attention to humus and fertility, are necessary to proper tree growth and nut production.
Lime breaks down vegetable matter and makes its constituent plant foods quickly available, but prevents a build-up of humus in the soil.
With proper conditions of moisture and aeration, sawdust, when mixed with quickly decaying material like kitchen garbage, can be reduced to an excellent, usable humus in three summer months.
Mr. Burgart's method has the advantage not only of guarding the trees from excessive winter injury but at the same time adds an almost immediately available source of humusand nutrients to the soil for spring growth.
Underfoot Paul felt a humus that might have been a thousand years in growing; he prodded it with his knife--a white worm curled in mimic death.
Two were hopelessly torn; he dug a hole in the humus and dropped those in, smoothing the surface, wondering at his need for an act which could mean nothing to the unhappy morsel of perception on the tree trunk.
They also greatly facilitate the downward passage of roots of moderate size; and these will be nourished by the humus with which the burrows are lined.
This earth forms the dark-colored, rich humus which almost everywhere covers the surface of the land with a fairly well-defined layer or mantle.
In estimating the value of artificial manures the chemist's dictum is of the greatest value, but his analysis when used to gauge the value of the living humus may be entirely misleading.
One hopes also that those who would condemn as foul the humus which contains a large amount of carbonic acid will remember that this gas may only be an evidence of perfectly healthy and vigorous action.
The conversion of the dead organic matter into humus is a biological process, and is caused by the animals which live in the humus, and is perfected by the growth of fungi.
Nature turns all the excrement to humus, and humus is acknowledged to be the very best purifier of offensive nitrogenous matter which the world affords.
The humus is the most perfect purifier and the best of filters, in virtue of its physical conditions and the life that is in it.
This world would not be habitable were it not for thehumus with which its bare rocks are clothed.
The best evidence that the humus is alive is the fact that it breathes.
On the other hand, my experience leads me to say that it is very difficult (if it be possible at all) to wash fæces out of well-tilled humus by any rain which we get in this country.
It must be recognised that in times of flood with a drowned humusthe power of purification may be lessened.
If the burning-up of humus and the leaching of the soil could be prevented, there is no reason why a cotton soil should not produce good crops continuously for an indefinite time.
The result is a great destruction of thehumus of the soil, and great leaching and washing, especially in the light loams of the hill country of the United States.
Soil usually contains more or less dark, carbonaceous, decaying organic matter, called humus, and is then often termed the humus layer.
Thus there is accumulation of humus and a decomposition of the rock proceeding together, and a loam of some sort is the result.
These are supplied almost entirely from the atmosphere itself, though, to a limited extent, the presence in the soil ofhumus or vegetable matter contributes also.
Calcareous soil is by no means unfavourable to Asparagus; still, a sand rich in humus is not the less to be desired, as the finest samples of European growth are the produce of the districts around Paris and Brussels.
Humus when it decomposes gives off carbonic acid, which breaks up the mineral substances in the soil and renders them available as plant food.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "humus" in a variety of sentences. We hope that you will now be able to make sentences using this word.
