genus
Knotweeds
Polygonum
Field notes
Children
Range
Greener is more native, amber more introduced; paler is less certain. How this was decided
Key traits
From USDA PLANTS.
Top native knotweeds All
Native to the US, ranked by caterpillars, then bees and other hosts, food, flowers and shelter.
-
Douglas' Knotweed
Polygonum douglasii
caterpillars
35
food
44
flowers
14
-
Bushy Knotweed
Polygonum ramosissimum
caterpillars
32
food
46
flowers
16
-
Leathery Knotweed
Polygonum achoreum
caterpillars
31
food
42
flowers
14
-
Small's Knotweed
Polygonum buxiforme
caterpillars
28
food
40
flowers
16
-
Milkwort Knotweed
Polygonum polygaloides
caterpillars
28
food
39
flowers
13
-
Slender Knotweed
Polygonum tenue
caterpillars
27
food
41
flowers
16
-
Sea Knotweed
Polygonum glaucum
caterpillars
27
food
36
flowers
15
-
Erect Knotweed
Polygonum erectum
caterpillars
25
food
36
flowers
11
-
Broadleaf Knotweed
Polygonum minimum
caterpillars
20
food
38
flowers
6
-
Scatter Knotweed
Polygonum spergulariiforme
caterpillars
18
food
35
flowers
5
-
Beach Knotweed
Polygonum paronychia
caterpillars
17
food
34
flowers
5
-
Wiry Knotweed
Polygonum majus
caterpillars
17
food
34
flowers
5
-
Nuttall's Knotweed
Polygonum nuttallii
caterpillars
16
food
33
flowers
5
-
Sawatch Knotweed
Polygonum sawatchense
caterpillars
15
food
38
flowers
3
-
Fowler's Knotweed
Polygonum fowleri
caterpillars
15
food
33
flowers
5