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Show FARM AND ORCHARD. Valuable Suggestions to the Producers. PARASITES OF THE 1ELLQW SCALE. Interesting Notes Por the Farmer aud I Orchardist. In the year 1S7"2, an extensive orange grower in the San Gabriel Valley pur-i pur-i chased several Bmal I orango trees al a 1 San Francisco tree depot, and planted them in his grove with the intention of ; budding from them, if the varieties : proved desirable, as previous to that ! most of the citrus trees in California were grown from seed and allowed to bear fruit aB seedlings. The trees were found to bo iufu.-ted with a sride insect of a species of Aspidiotus, which spread ; I to the adjoining orange trees, and their presence was detected by the mottled, 1 sickly appes ranee of the leaves and fiuit. A determined effort was made to check its spread and, if possible, slump it out, and the trees in the infected portion por-tion of the grove ere cut baik , the brunches burned, ami the trunks and limbs scrubbed; but after all this heroic treatment enough scale 3 escaped to in leBt the district. To distinguish it from the "brown scale," Locuiiium husperidum , and the "black scale," I, olea (the only sea ott that were then attracting attention in the r-tale), it was named the "red scale," fiom us reddish-yellow shell, and was considered identical with the red scale of Australia, Aspidiotus uurantii, Mus-kell Mus-kell ; but unite reuontly specific differences differ-ences have been observed that prove it distinct, and it is now known as the "yellow scale" Aspidiotus citrimiH, Uo-quillett. Uo-quillett. Various solutions were sprayed on the frees ; sulphur ami other bubstitnees were inserted under the bark. und the small covered with short hairs, with tkeexcep tion of a strip commencing near the stigma and extending around the wing to nearly the opposite edge. Legs liut yellow. We will undoubtedly always have the yellow scu'e; but no doubt the trees and Iruit can be kept in a heulthy and clean condition by this parasite. 1 would therefore recommend the colouizution of it wherever the "yellow acu'e" is found. In two ioimer articles 1 have recommended recom-mended thai an etl'ort be made to colonize colo-nize this parasite Uon the true red scale, AHpidiotus anrantu; but, in A recent visit to the Villa grove, 1 hud conclusive proof that this will be impossible, or at least of no pruct'cul benefit. Mr. Cogswell Cogs-well called my attention to a different scale he had noticed upon 11 lime tree near the hotel. This iiroved to be A auiantii, and 1 advised t lie destruction of the infer-ted trees, as this (Hide wculd be a more serious pest to contend with ; for n thing but fumigation with hydrocyanic hydrocy-anic acid gun has been of any avail against it. 1 cannot ticcounl for its appearance ap-pearance there unless it has been taken upon an orange by a visitor to the hotel and the infested peel thrown under or unto the lime tree. The colonization of this pmamte will not be satisfactory to the orange-growers as was that of the Vedului cardiimlis, because we cannot see the laivu pick up the scale and devour it ; however, if they me introduced in an onmgu grove infested in-fested with yellow scale, Ihe lenoliciul results will be certain oven if not. immti-(1 immti-(1 i:i lei v observable, as was the case with the 'diliu. Hruiichcs should bo obtained ob-tained wilh m'ulc-infcstcd leaves from an orchard kuo.vii to contain parasites in numbers. This can be ascertained by plueim: a few infcHled leaves in r while paper box, closing them up tightly with a cover; and altera few days tho box and leaves should be examined with a magnifying glass this is really necessary; neces-sary; for even with good eyesight they will be overlooked, as ! hoy are so very minute if numbers are found, hnincliOH should be taken, ami the ends placed in boxes containing wet sand or soil ; this will keep the leaves fresh and allow the parasites to develop and hatch. Ab tho tranches dry up, others eun be procured and tho operation re nettled. The boxos should be placed under the trees in the shade, or he secured in f he branches, and so located in tho orchard that tho prevailing Hummer winds may aid materially mate-rially in their distribution. The Golden Chulcid, a new parnsifo (unnamed) is also workii g on the yellow scale, and is indeed very p oiiiising. It was first ohservod in liuarlo; but recently re-cently 1 received numerous specimens iroui un orcnaru near 1 ne iMonomuii tract, San (iu Uriel, mid also from an orchard in Alhamhra. It is vury interesting inter-esting to know that from tho infested branches received from these orchards non') of the Coceoptingiis citriiius wero batched, showing thai tho newer species in working by itself upon the sealo in tliot-e districts. Tine parasite is much larger than the other, and of a bright goldcu-yellow color. 801110 of the internal paranilos havo, like the M-aies l hoy attack, but ono generation gen-eration each year. This is the caso with the one upon the black scale, Locanium ole;e. Seventy-five per cent, of these scales are annually destroyed by a parasite, para-site, JhlophotJiiBtor California, Howard. This is a grout check to what would otherwise other-wise prove a very destructive scole ; but the parasite only deposits eggs in the mature scales and just about the time the latter contain eggs, so that tho twenty-live per cent. Unit escape the t parasites are.sultiuient to again infont the tree, from tho fact that each scale contains con-tains from seven hundred 10 ono thousand thou-sand egg-. But it will ho fully ten months befoio tho scales are developed enough to lie attacked by the Jiitopho-gasier. Jiitopho-gasier. This is not the ease with the parasite of the yellow scale. Thev are breeding all the time. 1 have found Lhem every month in the year, and a half-grown yellow scale is aniple food to develop and mature a parasite. Ai-.i:xani)i:ii Chaw, Quarantine Officer Stale Board of Horticulture, Hor-ticulture, San Krancisco. roots were seveied, und to the ends leading to the trunk vials were placed containing chemicals of various kinilH, in the hope that the roots would take the chemicals up, and destroy the scales ; but in a great many instances the trees were destroy d instead, and otheis injured in-jured and made unproductive by reason of the caustic or greasy properties of the washes then used. Iuthe meantime the scale wus slowly but surely spreading, , until now it is found in nearly all the ora ge-growing sections of the valley ai.d adjoining foothil a. In the spring of 18SJI, Mr. Caswell, of ! the Sieira Mudre Villa, informed me that, the ccale . were not as numerous in hie grove us they had Uen, hut he could not ucco.iut i n' tli-iir disappear nice. He brought li e ln:in lies infested with yellow kieale, iroin which L huiche I u number of ver small chulcid flies; this parasite, however, h:id been discoveied by Prof. 1). W. Coqnilleti two yeais previous, pre-vious, in ihe ixtciif-.ive moves of A. B. k A. S. Chujiimm ; bin as the improvement improve-ment in the condition of the trees was nioio nolieeiible in the Coggswell grove, I mn of the opiidon ih.a they spread from the latter to (he Chapman and other orehauls. Various theories have been advanced for the disappearance of the yellow t-cule in that t-eclion ; the principal one is, the excessive ruinhill of the winters of 188'.'-i)0. 188'.'-i)0. But this theoiy cm easily he exploded ex-ploded by the fact that we have had very heuvy 1 ains in previous winter.-, and again, the improvement was noticeable and commented upiii previous to the winter of 1881MI0 If ihe ruiiiB had caused the destruction of the scales, why iB it that the decrease is not all over the in letted section? 1 find that where the paasite baa only receully been found, or where I have been unable to find them at all, the yellow scales are as numerous as before. I have recently hatched them by the hundred from Bcale-infested leuves taken from an orchard wherein a little over a year ago the parasite was not known to exist. The presence of such numbers of parasitic insects even if they are 80 minute as hardly to be delected de-lected with the naked eye should be sufficient to convince even the most Bkf ptical that the scales are succumbing to "nature's remedy." The fact that the scales appeared to be on the increase last fall can be accounted for. That ii the time when our scale pests have every season tdiown the most increase, und that this wub noticeable in the orchards where the parasite haB been at work t he longest, is not very remarkable, as we have hud another identical case. When the cottony cushion cush-ion Bcale was euppoeed to be cleaned out of Bome groves, and consequently there wus no food for the Vedalia cardinalis, the latter disappeared, and a few of the former that escaped increased and caused considerable alarm; but they were soon destroyed when the growers placed a fresh colony of the ladybirds on their treeB, YELLOW SCALE PARABITK. Coccophagus citrinus. New species (original). Length one-fortieth of an inch ; wing expanse one-twenty-fourth of an inch. Antennae, aB long aB head and thorax, color yellowish and covered with short dark hairs, eight jointed, crape slender and Blightly curved, stout pedicel one-third length of scape, between pedicel pedi-cel and funicle are two very small rimr joints that form the elbow, joints three and four are the shortest, five and siv each increase in length and diameter; Beven is twice the length of eix, and eight is the same length as SQven, but narrower and tapering. Head is yellow ; eyi 8 black, ocelli bright red, posterior portion of head and pronotum are very dark brown. Thorax golden yellow; abdominal ab-dominal segments are very dark brown. Thorax golden yellow; abdominal segments seg-ments are dark brown, olmost black; wings are furnished with long marginal hairs; the Burface of the fore wings are |