Minnesota Department of Transportation

511 Travel Info

Project development

Environmental process | Environmental review | Vegetation

Vegetation process

Vegetation categories

Functional vegetation

Functional vegetation is planted or volunteer vegetation which is supporting the road infrastructure, assisting in maintaining safe road use conditions, or providing visual screens to and from adjacent properties. Vegetation functions include erosion control due to water or wind, water infiltration, blowing and drifting snow control, aesthetic qualities, and visual screens adjacent to residential properties and adjacent junk yards.

Protected plant species

Protected plant species are those listed under state or federal endangered species laws or are Witness (bearing) trees.

Landscaped vegetation

Landscaped vegetation are trees, shrubs, or perennial flowers planted as part of a landscape plan by contract or permit on MnDOT right of way. Landscape vegetation includes boulevard trees, highway landscaping, living snow fences, and screens to adjacent properties. Vegetation in this category may be considered to be functional vegetation as well.

Invasive plants/weeds

Invasive plants and weeds can be spread easily during construction projects.┬áThese include State listed noxious weeds (PDF) and other plants identified by MnDOT’s RVMU that are in limited populations but have the potential to spread and hinder turf establishment.

Weed populations are mapped as they are found with the EDDMaps application. Weed population data is updated twice a month, stored internally, and can be viewed with ArcGIS. Absence of populations within this dataset does not equal no weeds present, rather interpret as area has not been surveyed.

High-risk trees

Assessment of tree condition and health along the project area is needed to determine existing tree risk and forecast of tree condition and health during and post construction. This assessment identifies trees that have, or will have as a result of construction, “structural defects that may cause the tree or tree part to fail, where such failure may cause property damage or personal injury1”. The assessment assigns a risk level of low, medium, or high to the tree.

Native plant communities

Native plant communities are identified by MN DNR. These areas include remnant prairies, rare plant communities, and managed or restored prairies.

Potential permits and approvals

  • Permit: Possessing or taking of state threatened or endangered species
  • Permit: Possessing or taking of federal threatened or endangered species
    • Agency oversight: U.S. Fish and Wildlife Service
    • Legal Basis: Endangered Species Act of 1973, 16 USC Chapter 35 1531-1544
  • Permit: Transportation of noxious weeds across county boundaries
    • Agency oversight: Minnesota Department of Agriculture
    • Legal Basis: Minnesota Noxious Weed Law Minnesota Statute 18.76 to 18.91
  • Permit/approval: Transportation of noxious weeds within county boundaries (differs per county)
  • Permit: Removal of witness (bearing) tree
    • Agency oversight: U.S. Forest Service
    • Legal Basis: 18 USC 1858

References

  1. Urban Tree Risk Management: A Community Guide to Program Design and Implementation. Publication NA-TP-03-03; US Forest Service Web site

Appendix 1: List of minimum diameter and height measures for specimen trees

Genus/species Common name Rural tree diameter (inches) Conifer height (feet)

All species of residential/urban/street trees

All

All

 

Multi-stem measurement

All

treat as one tree, note individual stem diameter and number of stems below 4
feet

treat as one tree, note individual stem diameter and number of stems below 4
feet

Abies balsamea

Balsam fir

7

60

Acer negundo

Boxelder

20

 

Acer nigrum

Black maple

4

 

Acer platanoides

Norway maple

20

 

Acer rubrum

Red maple

10

 

Acer saccharinum

Silver maple

40

 

Acer saccharum

Sugar Maple

16

 

Betula alleghaniensis

Yellow birch

4

 

Betula nigra

River birch

10

 

Betula papyrifera

Paper birch

12

 

Carya cordiformis

Bitternut hickory

10

 

Carya ovata

Shagbark hickory

4

 

Catalpa speciosa

Catalpa

20

 

Celtis occidentalis

Hackberry

17

 

Fraxinus spp

White, Green, & Black ash

Record only ash that have been/suspected
treated for EAB

 

Ginkgo biloba

Ginkgo

28

 

Gleditsia triacanthos

Honeylocust

16

 

Gymnocladus dioicus

Kentucky coffeetree

8

 

Juglans cinerea

Butternut

4

 

Juglans nigra

Black walnut

20

 

Larix laracina

Tamarack

14

47

Malus spp

Crabapple

8

 

Morus rubra

Red mulberry

4

 

Picea glauca

White spruce

12

91

Picea mariana

Black spruce

5

60

Picea pungens

Co. Blue Spruce

13

60

Pinus banksiana

Jack Pine

10

50

Pinus nigra

Austrian pine

14

72

Pinus resinosa

Northern Red Pine

15

84

Pinus strobus

Eastern white pine

20

72

Populus spp

Balsam poplar, quaking aspen,
big tooth aspen

12

 

Populus deltoides

Eastern cottonwood, hybrid
poplar

40

 

Prunus serotina

Black Cherry

8

 

Quercus bicolor

Swamp white oak

13

 

Quercus spp (Red Oak
Group)

N. Pin Oak, E. Pin Oak, N. Red
Oak, Black Oak

15

 

Quercus alba

White oak

20

 

Quercus macrocarpa

Bur oak

26

 

Sorbus
americana/aucuparia

American Mountain Ash,
European Mountain Ash

5

 

Tilia cordata

Little leaf linden

13

 

Tilia americana

Basswood

23

 

Ulmus spp

Elm (not Siberian)

25