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carl}' as possible in the Spring, as soon as the ground becomes 

 workable, so that they may become established before the advent 

 of hot weather. The natural environment of these latter causes 

 them to be constitutionally adapted to germinate at a temperature 

 just above freezing point, and they will germinate as quickly 

 at a temperature of 35 dcg. F. as melons, etc., will at 65 deg. F. 

 Thoroughly drained soils, deeply cultivated and well pulverized, 

 not only warm up quicker after frost is out, but they come into 

 a tit state for sowing seed inuch sooner, and plants will grow 

 quicker on them, than is the case in connection with ground 

 which has had poor treatment. Autumn spading or plowing is an 

 important fundamental in obtaining the best soil conditions in 

 the Spring. 



Germination is liable to be prevented by seeds being sown in 

 contact with compound chemical fertilizers, acid phosphate, or 

 any other inorganic fertilizer containing acid. The chief injury 

 by chemical fertilizers in connection with germination appears to 

 be inflicted upon the embryo after germination has started rather 

 than upon the seed itself. Organic fertilizers such as stock yard 

 manures and ground bones do no harm either to the seed or to 

 the sprouting plantlet. Dissolved bones are liable to inflict injury 

 because they are dissolved bj' acid. ' 



The operation of sowing seed should not be carried on when 

 the soil is wet or sticky, as treading upon, or w'orking a soil in 

 that state always does harm as a condition is brought about 

 which excludes oxygen, and which will also cause it to dry into 

 hard lumps. 



Very soon after germination is under way the embryo is seen 

 to be practically divided into two parts, namely, an ascending 

 and a descending axis. Of the two extremes of these axes the 

 ascending one becomes the shoot or plumule, and the other the 

 root or radicle. The question will at once arise as to what causes 

 the shoot to grow upwards and the root downwards? To this 

 question there is no real answer, except to say that the cause is 

 unknown. Certain guesses have been from time to time made 

 as to the why of this characteristic in plant life, one of these 

 being that the growing of the radicle into the soil is brought 

 about by the action of gravity, or, as it is sometimes put, by the 

 exceeding sensitiveness of the tip of the radicle to surrounding 

 influences especially to gravitation, a condition to which the name 

 geotropism has been given, the root being said to be positively- 

 geotropic and the shoot negatively-geotropic. While there is no 

 plant organ more wonderful than the tip of the radicle and there 

 is no doubt about its extreme sensitiveness, equally as much may 

 be said as regards the shoot. Darwin wrote : "It is hardly an 

 exaggeration to say that the tip of the radicle, endowed as it is 

 with such diverse kijids of sensitiveness, acts like the brain of 

 animals." He could have said the same thing about the shoot. 

 It seems that Darwin's line of thought opens up more possibili- 

 ties tending to solve the problem as to ivliy the root grows down 

 and the shoot up, than anything else. While the existence ot 

 brain-power in plants may not be capable of actual scientific 

 proof, yet there are hundreds of facts connected with plant life 

 which give ample grounds for faith to believe that such power 

 exists. 



It certainly appears to l^e nothing but absurd to bring the 

 attraction of the force of gravitation into the question, for the 

 simple reason that this force acts equally upon all matter of the 

 same weight existing under the same conditions, and it would 

 therefore have the same pull upon the shoot as upon the root. 

 Another point is that different species have different methods of 

 root-growth, some have a tap-root which while growing down 

 very deeply into the soil when conditions render this possible, 

 also produces horizontal roots; others, after the tirst root has 

 gone down some way, grow their roots entirely in an horizontal 

 manner. Then again when the soil down to, or below, the roots 

 has become very dry, and which subsequently is watered so that 

 only a couple of inches or so is kept moist, the roots will turn 

 and grow upward for the purpose of reaching the moist soil and 

 obtaining the water the plant stands in such great need of. In 

 this action brain-power appears more in evidence than the force 

 of gravity. It is this characteristic of plants' roots growing 

 towards the surface when the latter is moister than the soil 

 below, which is why mere surface sprinkling does more harm 

 than good when artificial watering is practised. In watering 

 plants sufficient should be given at one time to soak the <oil to 

 the bottom of the roots. In this way, coupled with cultivation 

 when the surface has become dry enough, watering is not re- 

 quired at one spot more often than once a week in dry weather. 

 While therefore the reasons why in the germination of seeds 

 the shoot and the root will curve round in their efforts to grow 

 up and down respectively is unknown, the greatest success from 

 growing plants from seed is obtained by the grower first making 

 the environment in which the seed is placed of such character 

 that these movements are carried on as easily as can be so that 

 the final completion of the act of germination is accomplished as 

 qiiicklv, and with as little expenditure of energy as possible. 

 \\'i!h the establishment of roots in the soil and with the 



exposure of green leaves to light and air, germination is over 

 and the plant is able to gather and work up its own food from 

 outside. The next step is to consider how it obtains food and 

 assimilates it for its growth. 



In connection with out-of-door gardening, the cultivator has 

 the part of the plant's environment which lies licncath the soil 

 surface more under control than the part which lies above it. 

 Practically he can do nothing by way of changing the composi- 

 tion or temperature of the air or of the amount of sunlight, but 

 he can do a great deal in inlluencing and improving the fertility, 

 the mechanical condition, the drainage, and the aeration of the 

 soil ; all of these_ combined constitute the environment of the 

 roots. It is therefore of considerable importance to know some- 

 thing about the roots of plants as well as of the soil in which 

 they grow and collect the plant's food. Obviously the plant is 

 extremely dependent upon its surroundings or environment, the 

 more so because of its lack of the power of locomotion. There- 

 fore plant organs must estaldish certain definite relations with 

 things outside of themselves before they can work effectually: 

 and these necessary relations are called life-relations. For ex- 

 ample, green leaves are definitely related to light as they cannot 

 perform their peculiar work without it ; most roots must bo 

 related to the soil ; certain plants known as aquatics are related 

 to abundant water : some plants, such as parasites, are related 

 to other plants. Each organ, therefore, must become adjusted to 

 a complete set of relations. Three conspicuous organs, root, 

 stem and leaf, are concerned with nutrition and growth, and 

 most plants have at some period of their life another structure, 

 the flower, which is entirely concerned with reproduction. 



The roots of land plants serve to anchor the plant in the soil 

 enabling the stem or stems of erect species to grow upright, and 

 to supply the plant with water containing its dissolved food 

 materials. As above mentioned, the primary root develops from 

 the lower end of the hypocotyl : but not only do lateral roots 

 develop from this primary root, but they may also develop 

 freely from other parts of the stem. If the base of the stem of 

 a corn plant be examined a week or so after germination we 

 may see roots growing out from above the point at which the 

 stem was originally attached to the seed ; and if we pull up a 

 squash vine, or unslaked tomato plant, or others of similar 

 growth late in the Summer, we often find them rooted from the 

 stem at some distance from the original root. Lateral roots 

 originate in the internal tissues of the root or stem, and not 

 close to the surface as do buds. 



Most forms of roots are adapted for growing in the soil, but 

 there are some of which this is not true. Thus many orchids and 

 ferns have aerial roots which fasten the plants to the stem or 

 branch of a tree, and absorb moisture and food from the heavy 

 humid atmosphere of the forest ; other roots are what are called 

 adventitious, or accidental, like those of ivy, which enable the 

 plant to cling to the stem of, and climb up another plant : also 

 to cling and climb up a wall, etc. It is noteworthy that these 

 adventitious roots are not usually put forth until after the ivy 

 shoot is in place against the object it proposes to cling to. There 

 are also roots which are parasitic, like those of the mistletoe and 

 Qodder. which enter into the tissue of their host plant — which 

 aerial roots and ivy and orchids do not — and draw nutriment 

 from it. Another somewhat extensive group of roots are those 

 of aquatic plants, which are adapted to life in the water. 



In the case of all land plants the growing tip of each root is 

 protected by a cap of cells called the root-cap. This root-cap 

 consists of several layers of cells, the outer ones gradually dying 

 or being worn away as the tip of the root pushes through the 

 soil, and being replaced by new layers of cells which are con- 

 tinually growing beneath. The mass of cells forming the root-tip 

 is always resistant and compactly arranged within; but as the 

 cells are pushed outward, becoming old. and sloughed off by the 

 continual addition of new cells, they undergo gelatinization and 

 decay : this gelatinization is important as it no doubt acts as a 

 constant lubricant to make easier the course of the tip as it 

 progresses through the soil. 



In advancing through the .soil the root-tip does not move in a 

 straight line but has an oscillating motion which enables it to 

 take advantage of openings lietwecn the soil particles. Since the 

 soil offers more or less resistance to the growth of roots, it is 

 evident that the roots of plants growing in it cannot elongate 

 through their whole length at once. If we try to push a piece of 

 fine wire, say a foot long, into the lightest soil, holding it at the 

 end away from the soil, it will be found to be impossible on 

 account of the wire bending. .\s a matter of fact the "push'' 

 which is needed to force the root forward in the soil is confined 

 to a portion rarely more than a half an inch in length. 



The roots and minute rootlets which, in a complete root-system 

 arc readily evident to the eye. are. however, secondary with 

 respect to the relations wh'ch exist between the plant, the soil, 

 and the air and moisture the latter contain. When a plant's 

 root-systein is examined, organs smal'er than the fine rootlets are 



