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Prof. Albert Koebele, of the entomological division of the Federal Department of the Interior—the Bureau of Entomology not yet having been established—was sent to Australia, to try to find a check for the pest in the country from which it had come. He discovered a natural foe of the cottony cushion scale in the l'edalia cardinalis, a beautiful little red and black ladybird; collected it in quantities, and forwarded it to California, where it was distributed wherever the pest had made its appearance. A little later he introduced another species, Novius kocbelei; and some time afterwards Mr. George Compere, explorer for the California State Board of Horticulture, discovered and introduced Norius bellus and the Black Vedalia. These ladybirds, like all others of the numerous species-numbering perhaps two thousand of the great family of Coccinelidze, are predaceous in their habits, both the larvæ and the matured
VARIOUS SPECIES OF LADYBIRD AND THE PARASITES FROM WHICH THEY SAVED CALIFORNIA'S
$20.000.000 CITRUS FRUIT CROP. 1-4 inclusive represent lady birds and larvae: 5—7b, cottony cushion scale parasite; 7. twig infested
with cottony cushion scale.
from 1888, the occasion being the ravages of an Australian pest introduced twenty years before. This was the cottony cushion scale, which for a time threatened the very existence of the orange growing industry. Groves that were badly infested presented the appearance of having been exposed to a severe snowstorm. From the orange trees the pest spread to hedges, shade trees, wild shrubbery and forests, until it was feared that vast areas of the State would revert to desert conditions. Shipments of oranges dropped from eight thousand car loads in one year to six hundred the next. Thousands of trees were cut down and Jurned, but the rest had been so widely scattered and had obtained so firm a footing upon wild vegetation that attempts to check its ravages, even by these heroic measures, were hopeless.
THE TRUE PARASITE AND ENEMY OF THE BLACK SCALE-SCUTELLISTA CYANEA AND
RHIZOBIUS VENTRALIS. 1-2. scutellista cyanea: 3-3b, rhizobius ventralis
insects pouncing upon and devouring the scale insects and plant lice that form their natural food. Other foes of the cottony cushion scale, also introduced from Australia, are a dipterous parasite, known as Lestophonus icerya, and a hymenopterous parasite, Ophilosia crawfordi. These deposit their eggs in the grub of the injurious insect; and when the young develop they feed upon the tissues of the host, killing it in embryo. Through the operations of these predaceous ladybirds and internal parasites, the cottony cushion scale was brought under complete subjection. It is longer feared as a pest or regarded as a source of danger, so that in describing these species as the "beneficial insects that saved the citrus fruit industry of California, the State Commission of Horticulture indulges in no hyperbole or exaggeration. If anyone doubts whether it was worth while, it is sufficient to say that the citrus fruit. crop of the State amounts to something like 35,000 carloads annually, worth $40,000,000 in the Eastern markets, or half that when
THE INTERNAL PARASITES—1, 2. AND 3—THAT HOLD IN
BROWN APRICOT SCALE-5, 6.
3. 3a, comys fusca.
packed ready for shipment to those markets.
The successful fight waged by imported insect allies against this terrible menace to the citrus fruit industry convinced Californians that the scientific method of combating insect pests was to pit one form of insect life against another—to employ bugs for fighting bugs; and to that end the State Insectary was established. In 1891, the state legislature made its first appropriation of funds for a systematic search for beneficial insects—a search that Mr. George Compere, explorer for the California State Commission of Horticulture and for the entomological department of West Australia, has prosecuted in every quarter of the globe.
It is conservatively estimated that the minimum tribute annually levied by insect hosts upon American farmers is not less than ten per cent. of everything pro
FOUR SPECIES OF INSECTS-1. 2. 3. AND 6–TH SUBDUED
THE SAN JOSE SCALE--4-AND THE YELLOW SCALE-5. 1. aspidiotophagus citrinus; 2. apbelinus fuscipennis; 3. chilocorus bivulnerus: 3a, larva of same;
6. rhizobius lophantha,
duced from the soil, and that the annual introduction of new pests as it is to find havoc wrought by forest fires is less than means of suppressing the old. So a the damage to forest growth for which Quarantine Division is maintained, in insects are responsible. The checking of charge of Deputy Commissioner Dudley insect depredations, then, constitutes a Moulton, with headquarters at San problem in national conservation of far Francisco. Ironclad horticultural quargreater moment than many of the local antine laws require that transportation conservation issues that have occupied companies, corporations and individuals the attention of legislators and of the bringing fruits, plants or bulbs into the public. Secretary James Wilson, of the State give notice to the quarantine offiDepartment of Agriculture, estimated cials, so that an inspection may be made. the value of the farm crops of the No vessel is permitted to enter any port United States for the year 1909 at in the State without having its cargo, $8,876,000,000. But before the farmer even to the passengers' baggage, rigidly gathered his harvest, the insect armies examined by the horticultural quarantine exacted a toll that reduced the total by inspectors. Every tree, plant, bulb and at least $900,000,000!
package of fruit is taken possession of by California's elaborate and efficient these officials and carefully examined. organization for fighting insect foes is Those found free from the suspicion of under the supervision of State Commis- insect pests are promptly passed, and sioner of Horticulture, J. W. Jeffrey. It others are either fumigated or burned, is plainly as important to prevent the as circumstances make necessary. Even
an orange in the hands of a sick baby is regions on the Pacific Coast, proving likely to be taken from it, and the floral most injurious to pear; apple and peach tributes on the casket of a citizen who trees. In 1893, it made its appearance has died abroad, and is being taken home near Charlottesville, Virginia, and infor interment, are ruthlessly confiscated vestigation showed that Eastern nurseryand destroyed. Of course occurrences men had scattered it broadcast over the like these do not tend to make the horti- Eastern and Southern States, through cultural quarantine officials popular; but the sale of plum trees obtained in the California has suffered too much from San Jose district. pests that came in accidentally and un- Before investigation was begun to denoticed to run any avoidable risks. termine from what country the San Jose
Horticultural regulations in the vari- scale had been introduced, Mr. Lick ous counties are equally strict. Each died. It being impossible to ascertain county has a horticultural board, com- whence he had secured his plants, exposed of three members. This board tensive explorations were made by Mr. appoints local inspectors to any number Marlatt, of the Department of Agriculthat conditions appear to require; and ture, in order to find the natural habitat has authority to order an inspection of of the pest, as it was anticipated that its any orchard, nursery, trees, plants, vege- natural check would be discovered there tables, fruit, packing house, storehouse, also. Its true home was at last found, in salesroom, or any other place or article the neighborhood of Pekin and Tientsin, that may be suspected of being affected China, where its enemy was discovered with injurious insects, and to take steps in the Asiatic ladybird-Chilocorus simto abate any pest found. It is required ilis. A number of these ladybirds were that all orchards be inspected at least imported, and the species has been bred once a year; that all horticultural in- to a considerable extent for the purpose spectors shall be versed in entomology, and that they be instructed in the duties of their office by a competent teacher. As Superintendent Carnes, of the State Insectary, was conceded by all to be best fitted by temperament and attainments for such a task, he was detached from the Insectary many months ago, by appointment of Governor Gillette, to membership on the Board of Horticultural Examiners. This made it necessary for him to devote his time exclusively to the preparation of an extended series of questions for each county, and to conduct a separate examination in each county, of candidates for the position of horticultural inspectors. During his absence the responsible head of the State Insectary is Frederick Maskew, Acting Superintendent, to whose courtesy the writer is largely indebted for material used in the preparation of this article.
Mr. James Lick, of San Jose, California, was a plant lover, and introduced many foreign plants, shrubs and trees for the ornamentation of his grounds. In the early seventies, the pest that became known as the San Jose scale, appeared on trees belonging to him, rapidly spreading to other orchards in the neigh
A Home for BENEFICIAL INSECTS. borhood, and later to all deciduous fruit
Interior of glass-walled room in which imported destroyers
are kept for observation and study.
of checking, if possible, the
eggs in those of the scales. pest in the Eastern United
Then the trees are boxed up States.
again, conveyed to the seaHowever, in California a
coast, shipped across the ocean native parasitic insect, the
in cold storage, and taken to Aphelinus fuscipennis, adapted
the State Insectary. There the its taste to the San Jose scale ;
trees are unboxed and placed and, finding the food supply so
in a breeding room, where deabundant, increased with ex
velopment is rapid, owing to traordinary rapidity, so that it
favorable conditions of light, has brought the dreaded pest
heat and ventilation. In this well under control. It still
manner the parasite of the breaks out from time to time
purple scale on citrus fruit in unexpected places, but the
trees was introduced from the shipment of a few colonies of
interior of China. its parasitic foe from the In
One of the first points for sectary suffices to check it be- A-HUNTING THE LADI- determination at the Insectary, fore it becomes a menace, so
when a new beneficial insect is that it is no longer feared.
received from abroad, is This is one of the rather rare instances whether or not it is affected by a secondin which a native beneficial insect has ary parasite. That every form of life adapted its taste to an imported pest. has its natural check is just as true of
Among other once serious pests that beneficial insects as it is of pests, so that, are now completely controlled by insect while there is little poetry, there is a checks may be mentioned the soft brown great deal of truth in the screed : scale on citrus fruits and the brown scale "Big fleas have little fleas of the apricot, of which the natural Upon their backs to bite 'em; checks are the two internal parasites, And little fleas have lesser fleas, Encyrtus flavus and Comys fusca. In And so ad infinitum.' May of the present year, Mr. Maskew It is evident that if a secondary paracollected in the breeding cages of the site were introduced along with the Insectary, and shipped to endangered beneficial insect, to prey upon it and orchards, an average of no less than limit is increase, the very object in view 12,000 flies of the last named species in its introduction would be defeated. daily for a considerable period. The The breeding of insects in any quantities black scale that once appeared to desired is a much less difficult underthreaten the very existence of the olive taking than might be supposed. It is orchards, and that constituted a serious mainly a question of food supply, tempest on citrus and many varieties of perature, light and ventilation. deciduous fruit trees, is fairly well con- "It is a conservative estimate,” said trolled by an Australian ladybird, and Mr. Maskew recently, "that one half of a small internal parasite introduced all the children now in California will through Charles P. Lounsbury, from some day be fruit growers, or the wives South Africa.
of fruit growers. If some of these can It may be inferred that to import live be given a fair idea of what we are trybeneficial insects from China, Australia ing to accomplish here, of the means or other remote countries is sometimes a necessary to the accomplishment of our matter of no small difficulty. Sometimes ends, and of the importance of the work it is necessary to pot small trees infested we are trying to do, to the agricultural with a scale pest, box
and horticultural interests .them carefully, and ship
of the State, there will be them to the distant coun
fewer obstacles in the way try in which the enemy of
of the parasitologists who the pest is found. There
come after us.” So, perthey are unpacked and ex
haps, not the least imporposed to the action of the
tant work of the Insectary