Pink and Green Aphid of Potato by Edith M. Patch follows a small garden insect through a surprisingly complicated life. Issued by the Maine Agricultural Experiment Station in October 1915 as Bulletin No. 242, it combines outdoor observations with work in the insectary.
Patch begins with a problem that matters to both research and crop protection: an insect may use different plants at different seasons and may accept many additional hosts. Understanding only the time it spends on potatoes leaves much of its life unexplained.
Following the insect through the year
The life-history section describes the aphid’s seasonal movements and successive generations. Rose bushes, potato plants and other food plants appear as parts of a connected annual history.
Patch distinguishes forms that bear living young from the forms associated with overwintering eggs. The account considers when winged individuals appear and how their movements can establish colonies elsewhere.
These pages give the bulletin a broader interest than a description of feeding damage. They show an observer trying to follow one insect beyond the crop on which it first attracted attention.
Economic importance and identification
The economic discussion reports heavy infestations in Maine’s potato-growing districts. It considers injury to young growth and the resulting effect on the plant.
The description identifies the species under the name Macrosiphum solanifolii. Both pink and green forms are discussed, with attention to color, body structure and differences between winged and wingless individuals.
Measurements and details of antennae, cornicles and other structures are included. These are useful to readers studying early aphid taxonomy, although the scientific name and descriptions should be compared with current references for identification work.
The bulletin explains why size or color alone can be misleading. Host plants and growing conditions can influence appearance, making knowledge of an insect’s history valuable when interpreting a collection.
What the insectary made visible
The indoor studies follow colonies on potatoes and alternative plants. Patch records dates, the condition of plants and the movements of the insects as food changed or became less suitable.
The sequence includes observations of aphids leaving old growth and establishing themselves on younger material. It also considers how confinement can affect the choice of a food plant.
This part is especially valuable as a record of research method. The reader sees how small observations, repeated over time, helped connect apparently separate generations and host records.
For natural-history readers, the account offers an example of patient observation with a specific question in mind. It does not reduce an insect to the short period when it is most conspicuous in a field.
A wide range of food plants
A separate list groups recorded food plants by botanical family. Cultivated crops and other plants occur together, showing why the author regarded the host range as a central difficulty.
The notes discuss the relationship between the potato aphid and material previously identified from other hosts. A literature section brings earlier descriptions and reports into the account.
These pages help explain how agricultural entomology depends on both field knowledge and the interpretation of earlier records. A plant list can become evidence in understanding the identity and seasonal behavior of an insect.
Natural controls and historical remedies
Patch gives natural controls their own section. Weather, predatory insects and parasites appear as influences on the size of aphid populations.
The remedial discussion considers clean culture and sprays, including tobacco preparations of the period. Those chemical recommendations are historical material and should not be used as current instructions for treating a food crop.
Illustrations toward the end show damaged plants and enlarged structural details. They make the connection between a colony of tiny insects and its effect on visible growth.
Reading the digital copy
This free ebook suits readers interested in garden insects, life-history research and the work of early experiment-station entomologists. Its chief strength is the effort to explain the whole seasonal cycle rather than only one outbreak.
The PDF contains 23 digital pages, including blank leaves, the original title page, staff information, text and illustrations. Printed pagination runs from 205 to 223. The scan retains aged paper and small type; enlarge the measurements and drawings for close study.
Book details
- Author: Edith M. Patch
- Publisher: Maine Agricultural Experiment Station, Orono, Maine
- Year: 1915
- Edition: Bulletin No. 242; October 1915
- Digital length: 23 PDF pages
- Language: English
- File size: 0.95 MB
