Weed Science quiz

More questions about Weed Science

These visible examples show the question style. LearnClash turns the full topic into ranked duels and spaced repetition.

1. 1 Easy

   What process uses weeds to clean up heavy metals from soil?

   Answer: Phytoremediation

   Why: Horseweed, a common weed, takes up lead, copper and zinc from soil, and it passes the hyperaccumulator threshold for copper.

2. 2 Medium

   How many years can common mullein seeds stay viable in soil?

   Answer: About 100 years

   Why: Botanist William Beal buried seed bottles in Michigan in 1879, and about a century later one common mullein seed still sprouted.

3. 3 Hard

   How does resistant horseweed protect itself from glyphosate herbicides?

   Answer: Sequestering it inside vacuoles

   Why: Cold breaks the trick: chilled resistant horseweed pumps far less glyphosate into its vacuoles, and a normal dose finally kills it.

4. 4 Easy

   How does organic mulch suppress many weed seedlings?

   Answer: It blocks sunlight from reaching seeds

   Why: Wood chip mulch needs 3 to 4 inches to keep the soil dark, and once it rots down weeds start sprouting in the mulch layer itself.

5. 5 Medium

   What term describes weed growth boosted by a low herbicide dose?

   Answer: Hormesis

   Why: Hormesis is why underdosing backfires: 5.6 g of glyphosate per hectare more than doubled seeds per plant in resistant fleabane.

6. 6 Hard

   What structures do parasitic plants use to invade their hosts?

   Answer: Haustoria

   Why: Once dodder's haustoria form, its own root in the soil dies and the plant lives entirely off its host.