CHAPTER II

COLLECTING AND STORING TREE SEEDS

Owing to the war there is little doubt that for several years to come adequate supplies of seeds and young forest trees will not be available from their usual sources on the Continent. Vast quantities of both are annually sent to this country from Germany alone, while from other parts of the Continent coniferous seeds in particular are largely imported—in fact, we are almost wholly dependent for both seeds and seedlings on foreign supplies.

Under these circumstances, it behoves the owners of woodlands in every part of the country to collect seeds, particularly of such trees as our plantations are mainly composed of. After these have been properly harvested, they should be stored away in suitable places till seed-sowing time in the spring. To some extent this will be a new forest industry, though for long, the seeds both of Scotch Pine and various hard-wooded trees, particularly the Oak, Ash and Elm, have been annually collected on various estates throughout the country, and the young plants raised from such stock have given every satisfaction when planted out permanently.

For several reasons, however, we cannot compete with foreigners either in the production of seeds or in raising young forest stock. For some years to come, owing to the uncertainty of supplies from abroad, both seeds and seedlings are bound to be scarce and expensive.

In the past, far too little attention has been bestowed on the collecting and harvesting of the seeds of trees and shrubs, the result, in not a few cases, being weak and unhealthy plants and an uneven and irregular crop. The best seeds, it should be remembered, are those collected from healthy trees in the prime of life, and grown under conditions favourable to their perfect development. An unhealthy tree will often bear a heavy crop of seed, but although the inducements to collect such are great, they should be discarded, those from the most robust specimens in the prime of life being chosen in preference.

Regarding the best way of collecting tree seeds little need be said, the exigencies of the case determining the best method to be adopted. The seeds of not a few trees may be collected as they fall, and this is especially the case with those of the Oak, Beech, Elm, etc., all of which may be swept into heaps and gathered in quantity from beneath desirable trees.

In the case of the various Coniferæ this method of seed collecting will not answer—indeed, in the majority of instances, the seed should be gathered, or rather picked, from the trees just before they became fully ripe, as in falling they get loose from the cone-scales and are lost. When collecting the cones of coniferous trees, a long, light hooked staff with which to draw the branches towards one can conveniently be used to procure an abundant supply. A bag or satchel should also be in possession of the seed collector, into which may be put such kinds of cones as fall readily apart, as the seeds from these are easily lost. Sometimes, as in the case of rare seeds, and when only a few cones are borne near the top of the tree, the seed collector must have recourse to climbing; but, in such cases, in order to avoid injury to the bark, he should be provided with a pair of elastic shoes or slippers. Great care is required in the collection of such seeds as those of _Abies nobilis_ and _A. nordmanniana_, the cones, when fully ripe, falling to pieces on the slightest touch. This, however, applies equally to almost every species of Abies, whereas, with the Pines and Spruces, the cones remain intact for an almost indefinite period of time, even though the seeds may have fallen out on becoming ripe.

The proper harvesting of tree seeds rarely, except in the case of experienced nurserymen, receives sufficient attention, although this operation should be as carefully attended to as in the case of the seeds of any other form of crop. After being collected, the seeds of all trees, unless such as are mixed with sand for the purpose of rotting, should be thinly and evenly spread out in a sunny spot, until thoroughly dry. They may then be deposited in a cool, airy place, and in thin layers, until wanted for sowing. An occasional turning is all-important and should never be neglected. The smaller and less common seeds may, for convenience sake, be hung up in calico bags, but they, too, should be occasionally examined to prevent dampness and heating.

The number of plants of various kinds that may be expected from a bushel of seed of average quality varies very much, and may be approximately given as follows: Horse Chestnut, 2,500; Oak, 6,000 to 8,000; Spanish Chestnut, about 3,000; Walnut, 5,000; Norway Maple, 12,000; Sycamore, about 12,000; Ash, 14,000; Beech, 10,000; Elm, 1,000; Birch, fully 16,000; Holly, 17,000; Scotch Fir, 9,000. To 1 lb. of seed: Spruce Fir, about 9,000; Larch, 3,000; and the Cluster Pine, Silver Fir, and some others, from about 500 upwards.

For convenience in regulating orders for sowing, the following table will show at a glance the approximate and relative number of seeds of the various commonly cultivated forest trees contained in 1 lb. weight:—

Abies nobilis about 19,400 Abies nordmanniana ” 10,000 Ash ” 6,800 Beech ” 2,700 Douglas Fir ” 95,200 Horse Chestnut ” 36 Hornbeam ” 9,968 Larch ” 65,000 Lawson’s Cypress ” 131,400 Lebanon Cedar ” 10,800 Norway Maple ” 4,600 Oak ” 100 Pinus Austriaca ” 35,000 Pinus Laricio ” 43,000 Pinus Pinaster ” 12,000 Pinus Sylvestris ” 75,000 Spruce ” 64,500 Silver Fir ” 14,960 Sycamore ” 4,624 Walnut ” 36

These figures must only be taken as approximate, the seed of various trees of the same species seeming to vary in the number to the pound in a marked degree. The results of careful analysis of one or two kinds may be cited as examples. In one case the number of seeds in 1 lb. weight of Scotch Fir was 69,600, while in another it had increased to 90,600; and in the Larch the numbers were 33,900 and 68,000. These differences are, however, mainly due to the individual seeds being weightier in one case than in another, probably owing to the age and health of the tree from which they were collected, the situation and exposure to which it was subjected, etc. However, for all nursery purposes the above figures may be accepted as a fair standard.

The time of collecting and the after-management of the different forest seeds vary so much that a brief description of those kinds most commonly planted will be found useful:—

=Alder= seed should be gathered from the trees in October and sown in spring, say May.

=Ash= seeds are ripe in October, when they should be collected and kept in moist sand during the winter, and sown in March.

=Austrian=, =Corsican= and =Weymouth Pine= seeds are treated in every respect like those of Scotch Fir, varying the kiln heat according to the looseness of the cone-bracts.

=Beech= seeds are collected in October and November, placed in sand, and sown in April. The young plants are readily affected by frost, and the seed should, therefore, not be sown earlier than the time mentioned.

=Birch= seed must be collected from the trees just before it becomes ripe in August, otherwise it is scattered broadcast and lost for cultivation. March is the time for sowing.

=Cupressus Lawsoniana= seed is usually ready for collecting in October, but should not be sown before the first week in April.

=Douglas Fir= seed is, in most cases, readily removed from well-ripened cones by threshing or by pulling the cone to pieces, but, in some instances, particularly where the quantity is large, kiln-drying is resorted to. The seeds are ripe in December and should be gently watered and sown in May.

=Elm= seeds are ripe in June, when they may either be sown at once, or dried and kept in stock for planting in March and April.

=Hawthorn= seed, or berries, may be sown when collected, or the outer coating rotted off by keeping them during the winter in moist sand.

=Hazel= nuts may be collected in autumn and sown at once, or kept till spring.

=Holly= berries require to be placed in sand for about eighteen months so as to rot off the fleshy outer coating, and may be sown in March. The mixture of sand and berries, which should be about in equal proportions, must be turned frequently. They are usually sown with the sand in which they have been lying.

=Horse= and =Spanish Chestnut= seeds may be taken together, the method of collecting and sowing being very similar in both cases. They are ripe by the middle of October, and may either be sown at once or kept till spring. One seed to 4 square in. will be close enough.

=Larch= cones, when ripe, are of a rather bright brown colour and require to be collected from the trees. This should not, however, be done till spring, though occasionally they are gathered in December. They part with the seeds far more readily than those of the Scotch Fir, and consequently require less heat when in the kiln.

=Maple= seeds are ready for collecting about October, and should not be sown till the beginning of April.

=Mountain Ash=, indeed, all the Pyrus family and others of a like kind, require the berries to be placed in sand, and when the outer fleshy coating has rotted away they may be sown either in autumn or spring.

=Oak.=—The acorns may be gathered or swept from the ground in November, and either sown at once or stored away in a cool, dry place till Spring. One acorn to every 4 square in. will be ample in the seed-bed. Sow in spring or autumn.

=Scotch Fir= cones are better not collected till early in January, and the time may even be extended till March. When quite ripe they have changed from bluish-green to a light, grey colour. As the cones part tardily with the seeds, artificial means have to be resorted to, the cones being placed thinly over a kiln heated to a temperature of from 75° to 112°. They should be turned every third hour, and after about thirty hours the kiln should be cooled down and the cones extracted as quickly as possible. By beating with a flail the seeds are readily removed from the cones, but it is best to do this before the cones have cooled down or immediately they are removed from the kiln. The seeds are then swept together and collected, and stored away until wanted for sowing. When not required for sowing at once, the seeds should be thinly spread out on the floor and slightly moistened with water from a fine rose watering-can. They should then be turned about until perfectly dry before being stored away.

=Silver Fir= seed does not require much, if any, artificial heat to cause it to part from the cone. By placing the cones in the sunshine, and heating and turning freely, the seeds come out without much trouble. In all cases, however, wherever possible, it is wise policy to dispense with artificial heat or kiln-drying as, unless this is carried out most carefully, the vitality of the seeds is greatly impaired thereby.

=Sycamore= seeds are ready for gathering in October, but should not be sown till the end of March or beginning of April.

=Walnuts= are collected, when ripe, in autumn, and sown in late spring.

=Yew= seeds are usually washed of the pulpy matter before being sown.

In the case of large seeds, such as those of =Araucaria imbricata=, =Pinus sabiniana=, and =P. macrocarpa=, the best way is to cut the cones to pieces and carefully remove the seeds. This operation should be performed with great care, so that the hard seed coating may not be injured.

With conifers in general I have invariably found it the best plan to allow the seed to remain in the cones until wanted for sowing. By keeping the cones in a cool, dry place, and occasionally turning them over, there need be little fear but that the seeds will turn out well.