Agenda - Environmental Policy Board - 11/06/2006

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In area 4, 69.9% (256) trees are regeneration, though prickly ash is rarely larger than 4" DBH and grows more like a shrub. If we discount this species 55.5% (203) trees are regeneration and boxelder becomes the most common tree regenerating in this area. Table 9. Regeneration Diversity Species Count Percent Ash, prickly 53 20.7 Boxelder 49 19.1 Cherry, black 29 11.4 Oak, red 26 10.2 Oak, bur 23 9.0 Buckthorn 22 8.6 Cherry, ornamental 16 6.3 Aspen 10 3.9 Redcedar, eastern 8 3.1 Elm, Siberian 6 2.3 Elm, American 3 1.2 Other 11 4.3 Plot Data. The thirty, circular plots were intentionally located in a variety of areas to try to capture as much information relating to all tree species that might be growing in each subdivision in addition to some information about conditions at the site. Some were located in wetlands: others included lawns, driveways and gardens while others were entirely in wooded areas. Plot locations and the data collected at each plot have been submitted to the City as a GIS layer. Some information of note: 1. Common buckthorn was found at one-third of the plots 2. Honeysuckle was found at five plots 3. American elms are dominant or nearly so at three of the sites 4. Oaks are dominant at nearly on -half of the sites regardless of the fact that at none of three subdivisions did oaks account for as much as 30% of all trees. More on this information in the Discussion section. Discussion Three of the ten most common species found during this project are not native to Minnesota (Siberian elm, common buckthorn and Colorado blue spruce) and two are not native to North America (Siberian elm and common buckthorn). This is important because Siberian elm and common buckthorn are considered undesirable and invasive. Both tend to exclude more desirable species. Amur maple was not as common, but also fits this category. The plot data shows buckthorn at only one-third of the plots despite being one of the most common trees in the survey. This is due, in part, to many of the plots being located wholly or partly in lawns, where buckthorn is much less frequently found than in wooded settings. This means, however, that where it is found, it is plentiful and provides a substantial seed source for further spread. Two of the most common trees in Minnesota, aspen and paper birch, are not so common in the City of Ramsey. Only nine paper birch were counted despite its popularity as an ornamental tree. Historically, aspen is known to be a minor component in the fire -dependent ecosystems such as that which once existed in this area. Yet with the