Pareto Academy
Log inStart free
CAT VARCeasyRC · Ecology

The Value of Dead Wood

Updated 22 October 2026

Read the passage and answer the questions that follow.

1For generations, a well-managed forest was a tidy one. Fallen trunks were hauled away, dying trees were felled before they could topple, and brush was cleared from the forest floor. Dead wood was regarded as waste at best and, at worst, as a breeding ground for pests and a store of fuel for fire. The tidy forest looked healthy, and to an eye trained to value timber, it was.

2Ecologists now regard much of this tidiness as a costly error. A large share of forest species, by some estimates a fifth or more of those in certain temperate woodlands, depend on dead or decaying wood at some stage of their lives. Beetle larvae tunnel through it, fungi digest the tough lignin that few other organisms can break down, woodpeckers excavate nests in standing dead trees whose wood has softened, and salamanders shelter beneath logs where moisture lingers through the dry months. Many of these species are specialists, tied to a particular stage of decay, a particular species of tree or even a particular thickness of trunk. Without them, much of the material locked up in wood would stay out of circulation for far longer than it does.

3Specialisation explains both why tidying was so damaging and why recovery is so slow. A fallen log passes through a sequence of decay stages over several decades, and a beetle that needs heartwood already softened by a certain kind of fungus can use neither a freshly fallen trunk nor one that has crumbled into soil. A forest stripped of dead wood for a century cannot be repaired simply by scattering a few logs across it. What is missing is not dead wood as such but a continuous supply of it at every stage, and that supply depends on trees having been allowed to grow old and die where they stand.

4The benefits of dead wood extend below ground. As fungi break logs down, nutrients are released gradually rather than all at once, and the spongy remains hold water like a reservoir, helping seedlings through drought. Logs lying across slopes slow the run-off of rainwater and trap sediment that would otherwise wash into streams. Some trees establish themselves most readily on rotting logs, known as nurse logs, where seedlings are raised above competing ground plants and escape some of the pathogens that lurk in the soil.

5None of this means that dead wood comes without cost. In landscapes prone to fire, heavy accumulations of dry fuel can make wildfires more intense, and managers there face a genuine trade-off. But that trade-off is regional rather than universal, and it has too often been invoked to justify clearing in forests where fire is rare. A more defensible approach treats dead wood as a resource to be budgeted: retained by default, and removed only where a specific local risk warrants it.

Question 1 · Multiple choice (+3 / −1)

The primary purpose of the passage is to

Show the solution

Answer: B. argue that dead wood plays valuable ecological roles and should generally be left in forests

  1. Paragraphs 2 to 4 set out the ecological roles of dead wood, and paragraph 5 concludes that it should be 'retained by default'. That is B.
  2. A is too narrow: lignin is mentioned in a single clause of paragraph 2. D is too narrow: tidy forestry is only the starting point in paragraph 1.
  3. C is too extreme: paragraph 5 accepts that removal can be justified where a specific local risk, such as fire, warrants it.
Question 2 · Multiple choice (+3 / −1)

The passage mentions each of the following as a benefit of dead wood EXCEPT

Show the solution

Answer: D. increasing the timber yield of neighbouring trees

  1. A is in paragraph 2 (woodpeckers nest in softened standing dead trees). B and C are in paragraph 4 (logs hold water like a reservoir; nurse logs raise seedlings above competing ground plants).
  2. The passage never says dead wood raises timber yield; paragraph 1 links the timber-minded view with removing dead wood, not keeping it. So D is the exception.
Question 3 · Multiple choice (+3 / −1)

According to paragraph 3, scattering a few logs across a long-cleared forest would not repair the damage mainly because

Show the solution

Answer: C. specialist species need dead wood at particular stages of decay, which requires a continuous supply over decades

  1. Paragraph 3 says what is missing 'is not dead wood as such but a continuous supply of it at every stage', because specialists such as certain beetles can use only wood at a particular stage of decay. That is C.
  2. A is out of scope: pests appear only in paragraph 1, as part of the old view. B belongs to paragraph 5 and is not the reason given in paragraph 3. D contradicts paragraph 3, which says logs decay over several decades.
Question 4 · Multiple choice (+3 / −1)

The author's attitude towards the practice of keeping forests tidy is best described as

Show the solution

Answer: C. critical of it as a mistake, while acknowledging why it once seemed sensible

  1. Paragraph 2 calls the practice 'a costly error' (critical), yet paragraph 1 grants that the tidy forest 'looked healthy, and to an eye trained to value timber, it was' (understanding why it seemed right). That is C.
  2. A misreads the author, who calls the practice an error and says the fire argument is often misapplied. B is too harsh: nothing suggests its practitioners were careless. D ignores the clear judgement in paragraph 2.
Question 5 · Multiple choice (+3 / −1)

Which of the following, if true, would most strengthen the argument in paragraph 3?

Show the solution

Answer: D. Specialist beetles remain absent from formerly cleared forests decades after logs were added, but are present in nearby old forests that have always had dead wood at every stage.

  1. Paragraph 3 argues that adding logs cannot replace a continuous supply of dead wood across all stages of decay. D shows specialists missing where logs were merely added, but present where that continuity exists, which supports the argument directly.
  2. A concerns generalist fungi, while paragraph 3 is about specialists. B relates to the fire trade-off in paragraph 5. C, if anything, suggests some species can do without dead wood, which does nothing to support paragraph 3.

Full worked solution

  1. Paragraph 1 describes the traditional view: a well-managed forest is tidy, and dead wood is waste, a pest habitat and fire fuel.
  2. Paragraph 2 turns the view around: many forest species depend on dead wood, and many are specialists tied to particular decay stages, tree species or trunk sizes.
  3. Paragraph 3 uses specialisation to explain why tidying was so damaging and why a few added logs cannot fix it: what is needed is a continuous supply across all decay stages.
  4. Paragraph 4 adds further benefits: gradual release of nutrients, water storage, slower run-off and nurse logs for seedlings.
  5. Paragraph 5 concedes a real cost in fire-prone regions, but limits it to those regions and proposes retaining dead wood by default.
  6. Central idea: dead wood is an ecological resource, not waste; it should be kept by default and removed only where a specific local risk justifies it.