Abstract
Annual seed production of diffuse (Centurea diffusa) and spotted knapweed (Centurea maculosa) is reduced in dry years by a reduction in the number of viable seeds per seed head and increases when above-normal precipitation occurs by increase in the number of heads/flower stem. Seed production was approximately 1,000-fold that needed to maintain observed levels of infestation. Seedlings emerging in April had a high rate of survival with most plants flowering the following season, while those emerging after May 15 had a very low survival rate and almost no flower stem production the following season.
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Claims 6
Claim · model-written summary
Dry years reduce viable seeds per head and annual seed production in diffuse knapweed.
Verbatim
e0“Annual seed production of diffuse (Centurea diffusa) and spotted knapweed (Centurea maculosa) is reduced in dry years by a reduction in the number of viable seeds per seed head”
Claim · model-written summary
Dry years reduce viable seeds per head and annual seed production in spotted knapweed.
Verbatim
e0“Annual seed production of diffuse (Centurea diffusa) and spotted knapweed (Centurea maculosa) is reduced in dry years by a reduction in the number of viable seeds per seed head”
Claim · model-written summary
Above-normal precipitation increases knapweed seed production through more heads per flower stem.
Not reportedTaxon
Verbatim
e0“increases when above-normal precipitation occurs by increase in the number of heads/flower stem”
Claim · model-written summary
Knapweed seed production was approximately 1,000 times that needed to sustain observed infestation.
Not reportedTaxon
Verbatim
e0“Seed production was approximately 1,000-fold that needed to maintain observed levels of infestation.”
Claim · model-written summary
April-emerging knapweed seedlings had high survival and most flowered the next season.
Not reportedTaxon
Verbatim
e0“Seedlings emerging in April had a high rate of survival with most plants flowering the following season”
Claim · model-written summary
Knapweed seedlings emerging after May 15 had very low survival and almost no flower stems the following season.
Not reportedTaxon
Verbatim
e0“those emerging after May 15 had a very low survival rate and almost no flower stem production the following season”