Crop in Orchard No. 3.

That portion of the experiment orchard designated as No. 3 was set in the spring of 1912 and comprises a pruning test, a fertilizer test and a variety pruning test. Comparatively little fruit was expected from this orchard during 1914 as it was only the third summer after planting. Dry weather followed the setting of the fruit upon the trees in the spring of 1914, however, and all the fruit that set seemed to remain. Carman produced as high as four baskets per tree in some instances in Orchard No. 3 during 1914. Belle, Champion, Hiley, Connett and several other varieties also produced considerable fruit.

This was also true in other well cultivated orchards of the same age in the State.

It was not expected that there would be much fruit for study from the variety test in Orchard No. 3 until 1915 but enough was secured for preliminary work in 1914. A considerable number of varieties proved to be untrue to name, especially in the case of those not so commonly grown as standard sorts in this State.

PEACH LEAF CURL.

This disease of the peach appears annually with varying severity according to the weather conditions during March and April. During the past two years its attacks have been unusually severe about Vineland. There are two rows of trees across Experiment Orchard No. 1, which have not been sprayed with concentrated lime-sulphur for the control of the San José scale since 1908. They have received the usual summer spraying of self-boiled lime-sulphur that the bulk of the orchard has received, how

ever.

During the spring of 1913, the unsprayed rows were severely attacked by leaf curl and this was the case again in 1914. Fig. 20 illustrates an unsprayed Belle of Georgia and a sprayed tree standing within 15 feet of each other. The marked effect of spraying the trees with concentrated lime-sulphur is quite apparent. Fig. 21 illustrates the same trees after most of the diseased foliage had fallen from the unsprayed tree.

A large proportion of the fruit dropped with the foliage from the latter tree, and the yields of the two compared show that the unsprayed tree produced very little fruit, while the sprayed tree produced several baskets. The scale has never caused any damage upon the unsprayed trees but the attacks of the leaf curl alone make it necessary to spray the trees annually with lime-sulphur.

The horticulturist has found leaf curl occurring in practically all parts of the state at different times since 1906, with the exception of New Brunswick. Not a single leaf affected with curl has ever been discovered upon a peach tree at the College Farm, even though nursery stock has been purchased from many different states and localities and planted. Some lots of stock have been divided and trees planted at Vineland and High Bridge, as well as at the College Farm. From the fact that trees at Vineland and High Bridge developed curl leaf, it appears certain that the

spores of the disease must have been present at New Brunswick in certain seasons, and that the failure of the disease to develop is likely to be due to some climatic factor.

JUNE DROP OF PEACHES.

In the latter part of May or early in June a proportion of the fruit set commonly falls from the trees. This shedding or falling of fruit has been largely attributed to such factors as lack of pollination and insect and disease attacks. If eggs of the plum curculio hatch and infest a fruit it is certain to fall; severe feeding punctures by the same insect near the stem of the fruit may produce a similar effect.

At times other insects, such as the May beetle and the rose chafer, injure the fruits so that they are destroyed. The occurrence of frost after the fruit has set may cause it to drop. It is a common occurrence, however, to find a considerable amount of fruit falling to the ground without the slightest indication of insect or disease injury. These fruits are generally somewhat smaller in size than the fruits which remain upon the tree. Fig. 29 illustrates some of these smaller peaches ready to fall from the twig. The cause for these fruits being small and their failure to develop has been attributed to lack of pollination in most instances. This does not appear to be true, however, from observations and studies at the New Jersey Experiment Station.

It has been noted that these small fruits have developed from the smaller fruit buds upon the twigs. Figs. 24, 25 and 26 illustrate the variation in the fruit buds of the peach and their rate of development in early spring.

The work of Huber (pages 64-68) shows that the pollen in these smaller buds which also bloom later than the large buds, is just as viable as that of the larger buds except in instances where the twig is greatly deficient in vigor and it appears certain that as perfect pollination occurs with the smaller buds as with the larger. It is also known that the peach is generally self fertile.

During cold, wet, unfavorable weather at blooming time fruit may fail to set upon the peach from lack of pollination as previously reported by this division, but this is not believed to be the common cause of the small fruits which fall.

During the season of 1914, the horticulturist in co-operation with Mr. Carl Schwarze, of the department of plant pathology, made observations and tests to determine at what point in the development of the peach tree in early spring the reserve food or starch in the roots and branches of the tree is used up, and the tree obliged to depend upon the work of the leaves to support itself. Frequent starch tests upon roots and twigs proved that the reserve food supply was practically consumed by the time the young fruits were from one-half to five-eighths inch in diameter: Some variation occurred according to the health, vigor of growth and variety of the tree although it was not as marked as might be expected.

*N. J. State Expt. Sta. Rpt. 1913.

FIGURE 31.-Large and small peaches upon the same twig.

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Another fact commonly observed by peach growers is that rapidly growing young trees frequently lose a considerable proportion of their crop at the time of the June drop. On the other hand, if these trees have been checked a large amount of fruit is retained. Each developing fruit upon the twig must receive a certain amount of food or it fails to maintain itself and necessarily falls from the tree.

The first fruits that set have the advantage of a larger food supply than the late set fruits provided no injury to them occurs, and they indicate this by an increased size at first. If the number of early set fruits is large the late set fruits lack food and remain smaller and finally fall.

The first fruit buds upon a twig to bloom are those which have been the most favorably situated the previous summers and fall to receive plant food. If weather conditions are favorable at blooming time they continue to hold this advantage over buds less favorably situated.

If the development and retention of the fruit is a matter of food supply following pollination, we would expect to find considerable variation in the proportion of the drop according to the number of fruits set and the rate of growth of the tree.

The drop is more severe upon very succulent young trees, because much of the reserve food in early spring is used for leaf and twig growth instead of being devoted to the development of the fruit. Trees checked in growth commonly retain a large proportion of the set of fruit, because more of the reserve food is distributed to the fruits.

The percentage of dropped fruit may thus vary greatly according to weather conditions in early spring according to whether it stimulates or checks leaf and twig development. The same facts and laws are as true of such fruits as apples, pears and plums as with peaches, although the proportion of fruit that drops because of lack of pollination alone may be greater with some of the other fruits.

PEACH SHIPMENTS TO BOSTON.

The heavy set of peaches in all districts from Georgia north to New Jersey gave an early indication that proper distribution of the fruit would be an important factor toward the success of the season.

From the fact also that the crop in the New England states was light, Boston appeared to be a promising market for fancy fruit beginning about August 5 to 10, after the bulk of the Georgia shipments was over.

The location of one of the experiment orchards at Vineland has stimulated the development of the peach industry in that vicinity as noted in the annual report of the Station for 1913, and the season of 1914 appeared to be a most appropriate one in which to take up the matter of shipments of peaches in carload lots to distant points. As the season advanced, this promised to be a profitable as well as an instructive line of work.

The heavy crop of fruit within easy shipping distance of New York, combined with the general small size of the fruit, indicated that prices in that market would be low at the height of the season, so the matter of carload shipments to Boston was taken up with the Vineland Peach Growers' Association.