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BATTLE OF THE BUGS

173

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fornia.

series of natural
checks upon the
endless number and
variety of forms of
life, a fairly even
balance is main-
tained. But man,
in providing for the
wants of a complex
and highly artificial
civilization serious-
ly disturbs this nat-
tural balance or
equilibrium—to his
own undoing, un-
less that equilib-
rium can be re-
stored. This equi-

A TRAVELING "BUG
HUNTER.
E, K, CARNES.

FREDERICK MASKEW. librium may be dis- George Compere, of Cali- Superintendent of Califor- Parasitologist of the Caliturbed in various

nia's State Insectary. fornia State Insectary. ways. For example, in the Imperial Valley the natural life- sitic enemies to limit its increase, it balance has been upset by irrigation, propagates with inconceivable rapidity, bringing vegetation to luxuriant growth develops into a pest, and causes wideat a season when the whole region, in a spread destruction. When a pest of this state of nature, was a parched and burn- kind makes its appearance in California, ing desert. The ladybird beetle is native war is immediately begun upon it by to the valley, but it issues in January, means of insecticides, dips, sprays or when the various aphids indigenous to poisonous gases, in an effort to prevent the same region also issued, when nat- its spread and to limit its ravages. But ural conditions prevailed. But by irriga- while these crude and inefficient tion and cultivation the melon vines are chanical checks are not neglected, the made to grow in April and May, sup- parisitologists of the State Insectary are plying an abundance of food to the exhausting every resource at their comaphids, and causing them to multiply mand to find its natural check, introduce with the rapidity characteristic of that it into the State, breed it in sufficient order of insect life, at a season when numbers to be of use, and distribute it their natural check in that life-zone is where needed. Nature never makes a inactive. To restore the equilibrium, mistake, and never does things by ladybirds must be imported from the halves; and it is just as sure as-fate that snowy canyons of the Sierras into the for every insect pest there is a natural tropic fields of the valley.

check. To put it in another way; the more common, and usually Intelligence that created the universe is more serious, disturbance of the natural quite capable of running it, and never life-equilibrium is due to the importation gave to any form of life the power to of foreign insects. A new variety of destroy without placing a definite limit fruit, for example, is imported from upon its powers of destruction. The Australia, or Japan, or South America ; inistakes in the distribution of insect and it is quite likely that the almost species that bring widespread destruction microscopic eggs of some insect that are man's mistakes: not nature's. And thrives upon that fruit are brought along when man makes a mistake of that kind unnoticed. In its natural habitat that it is up to him to correct it by finding particular insect probably did no notice- nature's remedy. That is precisely what able damage, because its natural check the parisitologists of the State Insectary kept it within bounds; but in its new are doing for California. environment, with an abundant food The inception of California's plan of supply, and with no predaceous or para- campaign, to fight bugs with bugs, dates

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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 koebelei; and some time afterwards Mr. George Compere, explorer for the California State Board of Horticulture, discovered and introduced Novius bcllus and the Black Vedalia. These ladybirds, like all others of the numerous species-numbering perhaps two thousand—of the great family of Coccinelidæ, are predaceous in their habits, both the larvæ and the matured

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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 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 orange

THE TRUE PARASITE AND ENEMY OF THE BLACK

SCALE-SCUTELLISTA CYANEA AND

RHIZOBIUS VENTRALIS. 1–2. scutellista cyanea: 3-3b, rhizobius ventralis

and larva: 4-6, black scale; 5. black smut.

BATTLE OF THE BUGS

175

2

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 no 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

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THE INTERNAL PARASITES-1, 2. AND 3—THAT HOLD IN
CHECK THE SOFT BROWN SCALE-4-AND THE

BROWN APRICOT SCALE-5. 6.
1. encyrtus flavus; 2. coccophagus lecani:

3. 3a, comys fusca.

3.

3

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

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For SPECIES OF INSECTS-1. 2. 3. AND 6–That 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,

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BUGS BY THE MILLIONS. Shipment of 2,000,000 lady birds from California's State Insectary to the melon fields of the Imperial Valley.

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

BATTLE OF THE BUGS

177

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.

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 wbich imported destroyers

are kept for observation and study.

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