(A) Dutch Elm Disease.
The City Tree Inspector shall inspect premises and places within the designated Dutch Elm disease control area of the city as many times as practical or necessary to determine whether the disease exists.
(1) Elm Trees. Dutch Elm infected trees shall be those trees that show any stage of infection. Property owners with trees identified as infected with Dutch Elm from March 10 through September 15 shall be made to remove these elm trees within 20 days of the notification. Property owners issued notifications on infected trees from September 15 through March 10, shall have elm trees removed prior to April 1.
(2) Elm Wood. Dutch Elm infected wood, logs, or stumps shall be disposed of by burning, chipping, or removal to an authorized disposal site or if retained shall be debarked by April 1st. The stockpiling and storage of elm logs with the bark intact shall only be allowed during the period of September 15 through April 1st.
(B) Oak Wilt. The City Tree Inspector shall inspect premises and places within the designated Oak Wilt control area of the city as many times as practical or necessary to determine whether any disease exists.
(1) Oak trees. All oak trees within the designated Oak Wilt control area of the city diagnosed as having Oak Wilt should be isolated from neighboring healthy oak trees of the same species by chemical or mechanical disruption of common root systems to prevent root graft transmission of the Oak Wilt fungus.
(2) To control overland spread of Oak Wilt, the pruning of oaks shall be avoided during the most susceptible period of infection, from April 15 until July 1. If wounding is unavoidable during this period, as in the aftermath of a storm or when the tree interferes with utility lines, the person or entity pruning shall immediately apply a non-toxic tree wound dressing.
(a) Red Oaks. To prevent the Oak Wilt fungus from producing spores and to prevent overland spread of this fungus, any diseased material of the red oak group that wilt in July and August of one year shall be removed from both private and public property by April 1st of the following year.
1. Any branch greater than two inches in diameter of the red oak group determined to be hazardous and not salvaged shall be disposed of by burning, chipping, or removal to an authorized dump site prior to April 1st of the year following the appearance of symptoms. Dead standing red oaks that have advanced beyond the potential for spore production need not be removed except where they constitute a hazard to life or property as determined by the City Tree Inspector.
2. Stumps of trees of the red oak group removed due to Oak Wilt shall be completely covered, removed or debarked to the ground line to eliminate all possibilities of spore formation and overland disease spread.
(b) White Oaks. Trees of the white oak group (i.e. white oak, bur oak, bicolor oak) diagnosed as having Oak Wilt should be isolated by root graft disruption as stated in § 97.45(D) (Root Graft Disruption).
(3) Oak Wood. Any hazardous oak wood to be used as fuel wood or to be salvaged for other purposes must be debarked or completely covered by heavy plastic (4 mil or greater) from April 15 until July 1 of the year following the appearance of symptoms. After July 1 the wood does not need to be covered.
(C) Diagnosis. Diseased shade trees shall be identified by generally accepted field symptoms such as wilting, yellowing of leaves, and/or staining of wood under bark. The Minnesota Department of Agriculture tree disease laboratory or other laboratories capable of performing such services approved by the Minnesota Commissioner of Agriculture shall do confirmation testing, when determined to be necessary by the City Tree Inspector.
(D) Root graft disruption (barriers) at property boundaries. If the City Tree Inspector finds that Dutch Elm disease or Oak Wilt threatens to cross property boundaries or disease control area boundaries, the City Tree Inspector may require root graft disruption to prevent the spread of disease. If plowing or trenching is not possible due to terrain, location or buried utilities, the City Tree Inspector may require alternate control measures. These control measures will be in accordance with current technology and plans as may be recommended by the Minnesota Department of Agriculture, Pesticide and Disease Control, M.S. Chapter 1505. If, however, after the City Tree Inspector identifies the location for the installation of a barrier or alternate control measure, the City Tree Inspector further determines that the installation of the barrier or alternate control measure is impossible because of the presence of pavement or obstructions such as a septic system or other underground utilities, the City Tree Inspector may mark for removal all oak trees whether living or dead, infected or not and located between an infected tree and the marked barrier location. These marked trees must be felled and disposed of no later than May 1 of the year following inspection. The stump from such felled trees must not extend more than three inches above the ground or, if taller, must be completely debarked. Expenses related to the installation of such barriers and/or the removal of these trees is at the expense of the property owner.
(1) The charge, or any portion thereof, for any necessary root graft barriers or other control measures may be assessed against the property on which the root graft barriers or other control measures are placed.
(2) Because Oak Wilt is a community problem and because Oak Wilt control may benefit an entire neighborhood, the City Tree Inspector will require neighborhood participation, shall encourage cooperation, including cost sharing, in root graft disruption and other control efforts, especially where Oak Wilt is in danger of spreading across property boundaries.
(E) Transporting diseased Elm and Oak wood. Unless transporting elm wood or red oak wood to an authorized disposal site, it is unlawful for any person to transport within the City any bark intact elm wood or wood from the red oak group that is determined to be hazardous.
(F) Emerald Ash Borer (EAB). The city has an adopted Emerald Ash Borer Preparedness and Management Plan, (City Council Resolution 2011-158). The City Tree Inspector shall inspect premises and places within the city limits as many times as practical or necessary to determine whether the pest exists.
(1) Ash trees. EAB infested trees shall be those trees that show any stage of infestation. Property owners with trees identified as infected with EAB from May 1 to August 31 shall be made to remove these ash trees after August 31 of the same year and prior to May 1 of the following year. Property owners issued notifications on infested trees after September 1, shall have the ash trees removed prior to May 1of the following year.
(2) Ash wood. EAB infected wood, logs, or stumps shall be disposed of within Hennepin County, either by grinding to a small diameter (less than one inch in two dimensions), burning or burying. No ash wood may be transported out of Hennepin County due to a state ordered quarantine on transporting ash wood to help control the spread of Emerald Ash Borer.
(Ord. 2002-973, passed 5-28-02; Am. Ord. 2014-1170, passed 5-27-14)