
Study Guide for Silent Spring,
Environmental Science,
Chapter 8, “And No Birds Sing”
44. Using the following sequence, explain how the attempts to preserve the “stately elm” have caused the
destruction of many bird species. Sequence: poisonelm leavesdecaying elm leaves on ground
consumed by earthwormsrobins
45. The DDT not only killed adult birds, but also affected their ability to _______________________.
46. Other unintended effects of DDT: (a) killed other organisms that feed on earthworms, such as
__________________________________________________________________________
(b) killed treetop feeders that feed on insects in the elms, such as___________________________
(c) loss of “nature’s own safeguards or policemen”, p. 113 which means
_________________________________________________________________________
47. What alternative method does Carson say is more effective, safer and less expensive than using
DDT to kill the elm bark beetle? Note: It had already been proven effective in New York.
48. Explain how applying “the conservation of variety” to the plantings in cities could reduce the need
for pesticides. (p. 117)
49. (a) How did DDT affect the population size of bald eagles without killing the adults? (b) Why was
DDT used in the coastal areas where eagles lived? (c) Eagles stored up DDT in their tissues by eating
fish that lived in DDT-laden waters. The eagles had DDT levels as high as _________ per million.
50. Carson makes the point that the use of pesticides is a worldwide problem. As one example, what
agricultural practice in England led to the destruction of many birds in the late 1950s-early 1960s?
51. What is “one of the great blank spots in pesticide research everywhere”? (p. 125)
52. Carson proposes ANOTHER alternative to chemicals on p. 126. How could the farmers have
prevented the blackbirds from eating their corn without resorting to the poisoning of 65,000 birds? By the
way, she describes the parathion used as a “_______________ killer”, so the death toll among wildlife
would be ever higher.
53. Carson asks the question, “Who has the right to decide” to “set in motion these chains of
poisonings”? What is her answer in the chapter’s closing sentence?
Chapter 10, “Indiscriminately from the Skies”
54. Define the word indiscriminately using a dictionary, and eradication using p. 157.
55. The gypsy moth is a native of ___________________________ and had been successfully controlled
by the use of ______________________________________________________________________.
56. The citizens of Long Island sought unsuccessfully to stop the spraying of DDT in 1957. According to
Carson, what benefits came from their failed attempt? (middle of p. 159)
57. What were some unintended effects of the attempts to eradicate the gypsy moth? Was the
eradication program successful?
58. How and when did fire ants arrive in the U.S.? Are fire ants a serious threat, according to Carson?
59. What were some of the unintended effects of the attempts to eradicate the fire ant?
60. How was the milk supply endangered?
61. The chemical used to kill fire ants was heptachlor, which is now banned. What is “peculiar” about
this chemical, a fact that had been published prior to its widespread use?
62. What alternative to mass spraying of fire ants does Carson say is effective and less expensive?
63. Carson uses strong words to condemn the gypsy moth and fire ant eradication programs. She calls
them “the height of absurdity,” “ill-conceived,” and a “failure.” She also says, “Never has any pesticide
program been so thoroughly and deservedly damned by practically everyone except the beneficiaries of
this ‘sales bonanza.’” What group would benefit despite all of the short-comings of the program?