A very large number of gardeners deem protection of some sort necessary; a few declare against protective measures in any degree, and not very fairly comparing small things with great, class them in the same category with corn-laws and protective tariffs. The differences of individual experience are sufficient, no doubt, to account for some divergence of opinion as to the extent of protection necessary; but the almost universal prevalence of frost, or equally destructive winds, up till a late period in spring, should leave little room for doubt as to the expediency of the practice to some extent. Perhaps too much protection is as bad in its results as no protection; and thus the non-protectionists may find some justification of their views in the failures of those that coddle their trees, under the impression that they are retarding them, till they become unnaturally sensitive of every change that occurs in our fitful spring weather. It is quite possible to protect overmuch as it is possible to clothe ourselves overmuch. The Hibernian gentleman who put on his entire wardrobe, consisting of three suits and an overcoat, and yet felt cold, neither succeeded in making himself more comfortable nor in bracing himself up to a better state for enduring cold.

So with our fruit-trees; we may clothe them to the extent of frustrating our own object, and weakening their powers of endurance. Much ingenuity has been displayed in devising fabrics for the purpose of protecting fruit-trees. Some of these fabrics are well, others ill, adapted for the purpose; yet each has its advocates. Some prefer a dense or heavy covering, such as canvas or frigidomo, along with the attendant labour and trouble of daily removing in the morning and putting it on at night. Others think the lighter kinds of protecting materials, such as Haythorne's hexagon netting and the thinner kinds of tiffany, the most effective protectors for either blossom or fruit. Perhaps no kind of material in use for the purpose meets all the requirements. Haythorne's netting, the least dense and most elegant of all, is, I believe, too thick, too obstructive of light, and too bad a conductor. The object of protection should not be to increase artificially the temperature around our trees, but to prevent excessive loss of heat by means of radiation or blasting winds. A much slighter covering than any in use is sufficient to effect this.

It is no uncommon thing; to find a tender Peach or Apricot under an overhanging leaf quite safe, while those exposed directly to the action of radiation are destroyed. The thin leaf, with its tissues charged with moisture, is a pretty good conductor, yet it is quite suificient protection for the fruit it shelters, and the fact is suggestive. Some apply their protection long before their trees are in any danger, and believe they are retarding them. The use of this it is difficult to see; for supposing that it is possible with safety to retard trees that are stirred into activity, say in February or early March, by the slight increase of the mean temperature of day and night that takes place so early in the year, is the application of protection, as soon as they are suspected to be on the move, the proper means to adopt in order to accomplish this object? I am not satisfied that it is so, for having had some experience of most of the materials commonly used, I have observed that they all tend to increase the mean temperature of the day by raising the actual temperature of the night, while they have much less influence in depressing that of the day than is generally supposed.

The weather itself is perhaps the most effectual retarding agent we could wish in spring, north of the Tweed at least. But granting that the application of the most approved protecting fabric acted so as to retard the activity of the trees, what, it may be asked, is the good gained by the practice % Not much that is very apparent. Could we retard them for a month, which is impossible, we should not then be able to pronounce them past danger; for there are not any grounds for assuring ourselves that the more tender kinds of fruit - such as the Peach and Apricot - are safe till the middle or end of May. It is from March till the middle of May that danger to our fruit crops is most to be apprehended from frost; and it is pretty clear, I think, that it is impracticable to retard the action of the trees to any considerable extent, so as to tide them over the critical period in greater safety. Any covering, be it light or heavy, if it is composed of non-conducting material, will have the effect of surrounding the subject protected by it with a more equable atmosphere, less liable to fluctuations of temperature than the outer air.

Every cultivator knows that such a condition is the most favourable for steady progress in vegetable activity, and that plants accustomed to such a condition are much more susceptible of injury from any sudden decrease of temperature than those that are subject to greater variations. Those, therefore, that practise that system which is named retarding, practically extend the period of danger by hastening its commencement, for there is no possibility of correspondingly shortening it at the other end, and they also increase the danger by rendering their trees more susceptible of cold when extreme occasions arise. My own experience is all in favour of the thinnest possible protection, to be put on only when it is no longer safe to postpone doing so, and to be kept permanently fixed as long as protection is thought necessary. In my own case, circumstances leave me no choice between old herring-nets and nothing. During the past three years they have been used only in part for the purpose, there not being sufficient of other fabrics to cover all subjects deemed worthy of, or in need of, protection, but during the present year nothing has been used except old herring-nets. We use them twofold; and scanty protection though they may appear to be, we have proved them quite capable of carrying safely through as good crops as there are agoing this year of Apricots, Peaches, and the better kinds of Plums, etc.

Yet we were not exempt from the exceptionally severe weather that prevailed from March till the beginning of the second week of June: on the 15th March we had 17° of frost; on the 7th, 8th, and 9th April we experienced 6°, 9°, and 12° of frost each night respectively; and again, on the l6th May, we had 10° of frost. On these very severe mornings, and others less severe, but still frosty, which preceded and followed them, we, in addition to our preventive measures, employed also restorative means in the shape of cold water from the garden engine; the trees were kept drenched from peep of day till the sun had warmed the atmosphere. I believe this did much good; I am persuaded, at least, that it did no harm. Our thinnings of Apricots would have furnished the trees twice over with fair crops. Peaches will not bear thinning, but there is a respectable sprinkling on most trees. Plums are fair crops, and Cherries also are fair; Apples and Pears, neither of them protected, are exceedingly thin crops.

This subject of the protection of fruit in spring is interesting as well as important, and to many, I have no doubt, it would be acceptable to see it fairly discussed from various points of view.

W. Sutherland. Minto Gardens.