BETTER FRUIT 



OFFICIAL ORGAN OF THE NORTHWEST FRUIT GROWERS ASSOCIATION 



A MONTHLY ILLUSTRATED MAGAZINE PUBLISHED IN THE INTEREST 

 OF MODERN AND PROGRESSIVE FRUIT GROWING AND MARKETING 



SPRAYING FOR CURCULIO AND CODLING MOTH 



BY ESTES P. TAYLOR, MISSOURI STATE FRUIT EXPERIMENT STATION, MOUNTAIN GROVE, MISSOURI 



THE name plum curculio was given 

 this insect from its having been 

 observed in early days as a very 

 serious pest of the plum. It is a very 

 old insect in this country, having been 

 mentioned in literature as a pest more 

 than a century ago. 



Not only is its injury notorious upon 

 plums, cherries, peaches, nectarines, apri- 

 cots and other stone fruits, but it attacks 

 the apple, pear and quince, and of native 

 food plants it is to be found upon wild 

 plums, crab-apples and hawthorne. Dr. 

 C. V. Riley, the first state entomologist 

 of Missouri, studied the insect in this 

 state, publishing many of the details of 

 its life history in 1869. It was even as 

 early as this date that he recorded it as 

 injurious to apples. Thus it has been 

 known as an apple pest in Missouri for 

 forty years. It seems to have been espe- 

 cially destructive here on this fruit about 

 ten years ago, as noted by Dr. J. M. 

 Stedman in his excellent bulletin upon 

 ■'The Sting in the Apple," published in 

 -1904, and has evidently grown even more 

 destructive in recent years. In some 

 sections of the state, notably along the 

 ^lississippi River and in parts of the 

 Ozarks, it has been found by the writer 

 to cause greater damage to the apple 

 crop than the codling moth, and if the 

 insect is considered from the standpoint 

 of its damage to all fruits it is unques- 

 tionably responsible for greater financial 

 loss to Missouri horticulture than any 

 other insect present. 



Most orchardists are familiar with the 

 appearance of the adult. It is well illus- 

 trated in Fig. 1, where its different stages 

 are also shown. It is a grayish-black 

 "snout-beetle" measuring one-fifth inch 

 in length and bearing two prominent 

 humps and several smaller elevations 

 upon its back. The beetles are not easily 

 seen upon the trees, requiring very close 

 observation to find them. They have 

 the habit of other snout-beetles of drop- 

 ping to the ground when disturbed and 

 feigning death or "playing 'possum," as 

 it is expressed. Some orchardists take 

 advantage of this characteristic and cap- 

 ture them by jarring the trees in the 

 early morning over sheets or "curculio 

 catchers." The beetles pass the winter 

 hiding about the orchard, in adjoining 

 timber, beneath the rough bark of trees 

 and in other places of concealment. In 

 the spring, following the blooming of 

 fruit trees, they emerge from hiding 

 quarters and soon begin making their 



punctures upon the fruit. Peaches, plums 

 and cherries, being earlier to set fruit, 

 are usually attacked first. Apples are 

 stung first when about the size of peas 

 or a little larger. Two kinds of injuries 

 are made by the beetle, the round open- 

 ing through the skin made in feeding 

 and the small crescent or half-moon 

 shaped marks made partially surround- 

 ing the pit, where the egg has been pre- 

 viously laid. Sometimes the beetles feed 

 sparingly upon the foliage, eating small 

 holes in the leaves. 



Contents 



SPRAYING FOR CURCULIO AND CODLING 

 MOTH, 19 



ABSORPTION OF ARSENIC BY APPLES 

 FROM SPRAY, 28 



PREPARATION AND USE OF LIME- 

 SULPHUR SOLUTION, 30 



FUNGUS DISEASES OF FRUITS - 

 THEIR REMEDIES, 33 



INJURY CAUSED BY THE APPLE 

 POWDERY MILDEW, 39 



SPRAYING CALENDAR FOR 1911, 47 



EDITORIAL, 48 



PESTS UNKNOWN TO COLORADO 

 FRUIT GROWERS, 69 



The eggs hatch in from five to ten 

 days into a tiny grub, which begins at 

 once to bore minute channels through 

 the tissue toward the core or in irregular 

 tunnels leading through the flesh. The 

 larvae are yellowish white in color with 

 a light brown head. They are footless 

 grubs, rarely exceeding one-third of an 

 inch in length when fully grown. With 

 these characters in mind they need never 

 be confused with the larvae of codling 

 moth. 



From three to five weeks are required 

 from egg-laying to emergency of the 

 larvae from fruit. The pupa is formed 

 in an earthen cell rarely deeper than two 

 inches, and occasionally just beneath the 

 earth's surface. If undisturbed five or 

 six more days are spent by the larvae in 

 its earthen cell before transforming to 

 pupa, and from five to ten days are spent 

 as pupa. From two to four weeks are 

 spent from the time the larvae leave the 

 fruit to the time the new adult beetle 

 appears above ground, and from fifty 

 to sixty days represents the average 

 length of time spent in the summer 



for their complete development. These 

 periods may vary somewhat with the 

 moisture, temperature and other condi- 

 tions. There is but a single generation 

 throughout the year, the beetles which 

 mature during the summer making some 

 food punctures in the fruit before going 

 into hibernation, but not laying eggs nor 

 doing their principal damage in feeding 

 until they emerge from hibernation the 

 following spring. 



Apple growers will be interested in the 

 dates at which the different stages of 

 curculio may appear in the orchard, since 

 it is upon this that the spraying opera- 

 tions depend. Arbitrary dates cannot be 

 depended upon from year to year on 

 account of variations in weather condi- 

 tions, nor can they be expected to 

 exactly correspond for all parts of the 

 state the same year. Comparisons of 

 time of development of the insect with 

 that of the fruit is consequently of much 

 greater value. 



In 1908, at Olden, a point in the 

 Ozarks, at an elevation of about 1,200 

 feet, no adult curculio could be jarred 

 from apple on April 30. At this date 

 the calyces of Jonathan were well formed 

 tubes, and Ingrams, a late blooming 

 variety, had shed more than one-half 

 of their petals. However, at this time 

 beetles were to be found quite abun- 

 dantly upon peaches and plums. A 

 single beetle had been taken upon plum 

 April 1, nearly three weeks earlier. A 

 few egg and food punctures were found 

 on May 5 upon apples which measured 

 from one-fourth to one-half inch in dia- 

 meter. From the time apples measure 

 one-third inch in diameter to when they 

 reach the size of walnuts the maximum 

 number of both food punctures and egg 

 crescents are being made in them, a 

 fact which should be borne in mind in 

 directing sprays, especially against the 

 curculio. 



In unsprayed orchards a slight increase 

 in feeding punctures may be noticeable 

 generally late in June or early in July, 

 due to the emergency of the new genera- 

 tion of beetles. These new adults, how- 

 ever, feed rather sparingly in the late 

 summer, much less voraciously than did 

 their parent beetles in the spring, and 

 with less appetite than they themselves 

 will show the following spring. 



Under normal conditions, where the 

 over-wintering adults are not destroyed 

 by orchardists, they may also feed and 

 deposit eggs much later than indicated 



