Pennsylvania Smartweed and also Ladythumb (Polygonum pensylvanicumL. AndP. Persicaria L.)


Life cycle:

Summer annuals. Arise in the spring and collection seed in late summer/fall and die. Over there is additionally a perennial smartweed, swamp smartweed (P. AmphimbiumL.). The rhizomes room white and also thin; thus this weed is often referred to as "shoestring".

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Emergence:Pennsylvania smartweed and ladysthumb (smartweeds) arise in beforehand in the spring. Ten percent arise by 150 GDD (base 48 F).

Smartweeds emerge from floor depths of less than 1".

Seed:Production Average:Each smartweed plant produces an median of 19,500 seeds.

Dispersal Mechanisms:None.

Longevity:Smartwed particle exhibits middle persistance. It takes 4 year to minimize the seedbank by 50% and around 26 year to alleviate it through 99%. In one study, 3% that the smartweed seed quiet germinated ~ 10 years. In one more study 6% quiet germinated ~ 16 years.

Dormancy:Smartweed seeds is less dormant when the seeds is locate in the upper inch that the soil profile. As funeral depth increases, particle dormancy increases. Smartweeds need wet soil conditions to germinate; hot, dry soil conditions reason seed dormancy. Fresh seed are constantly dormant and require a cold period (winter) before being able to germinate the complying with spring.



Smartweeds are rather competitive, yet they space low growing weeds. Soybean productivity was reduced 13% through 8 smartweed plants in 30ft^2 of ar (about one plant every 4 feet of row). Smartweeds are an ext competitive in street beet.

Preferred soil / field Conditions:

Smartweeds prefer wet, poorly drained soils and those high in nitrogen and phophorus. They execute not tolerate drought conditions.



Tillage: tilling at night (dark tillage) will mitigate smartweed development by 30-50%. If perennial smartweed is current in the field, clean tillage equipment prior to moving to another field- the rhizomes will wrap and hang top top the tillage equipment.

Rotary hoeing: Hoe smartweeds before they exceed 1/4" in height.

Flaming: Flaming is effective on tiny smartweeds (less 보다 1" in height).


Crop rotation: Smartweeds room not a weed of small grains and also forages.

Planting date: mix in the feather triggers smartweed come germinate. Therefore, mix in early May and also planting later on (mid-May) will reduce smartweed infestations due to the fact that many smartweed plants will have emerged and also been controlled by tillage.

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Application timing and also effectiveness:Herbicides are obtainable to regulate smartweeds. Manage can be daunting in street beets.