Energy Performance Systems, Inc.

Project Title: Improving the Efficiency of Planting, Tending and Harvesting Farm Grown Trees for Energy Contract Number: RD-50 Milestone Number: 23 Report Date: 11/5/2010 Principal Investigator: L. David Ostlie Contract Contact: Same Phone: 763-428-0646 Phone: Same Congressional District: 3 (Corporate office: Rogers, MN) Congressional District: 7 (Project Farm location: Graceville, MN) Congressional District: 6 (Equipment Building Location: Big Lake, MN) Executive Summary: Energy Performance Systems, Inc. Owner & Developer of the Whole Tree Energy Technology MILESTONE 23 - SUMMARY REPORT Annual Tending and Monitoring of Trees Hybrid poplar plantings established near Graceville, MN were monitored October 25, 2010 for 4 th year growth on the 80 acre site and for 3 rd year growth on the 10 acre site. Growth was excellent on areas of the fields that did not suffer from unsuitable soils conditions or from establishment year problems such as poor cutting quality and excessive weed competition. The canopy was completely closed in many portions of the 4 th year planting and moving toward closure in much of the 3 rd year growth stand. Growth in 2010 on the 4 th year plantation doubled the cumulative growth seen in the first 3 years. Standing biomass in October 2010 averages 14.6 total oven dry tons/acre (equivalent to 3.65 odt/acre/year). The stand has not yet reached maximum current annual increment so it is expected that growth will continue at an accelerated pace for at least one more year. Growth in 2010 on the 3 rd year 10 acre production trial in Dumont was good but the average 3 rd year standing yields of 5.5 total oven dry tons/acre (equivalent to 1.84 odt/ac/year) suffered due to damage from snow loading of up to ten feet high a few rows in from the north boarder and apparent problems with soil quality. Aerial photographs show distinct differences in growth associated with specific rows. Tending of the fields consisted of trimming trees with main stems that had been broken during the winter of 2009, mowing for problem weeds (thistles) on portions of the 80 acre site, boarder and spot spraying Stinger on the Dumont site and establishment of a fertilizer trial on the 80 acre site and the ten acre site. Growth measurements taken inside the fertilizer plot are very similar to those outside the plot, so no effect of the fertilizer can be detected. Near infrared aerial photographs taken in early October of the measurement plot areas confirm that no fertilizer effect can be detected. Improvement in growth compared to 2009 may be largely attributed to the higher number of growing degree days, and more sunny days along with adequate rainfall. Some trees in the 5 acre clone variety testing plot are performing extremely well given the deer browse issues and weed competition that occurred in the first 2 years of growth. Height and diameter of the best cottonwood clones planted as rooted stock and NM6 planted as slips in the clonal trial appear to be similar to that measured in the best areas of the Dumont production site. FAX 763-428-0647 1 of 19

Technical Progress Milestone 23: Annual Tending and Monitoring in fourth year of project. Introduction This milestone report includes 4 rd year growth measurements and yield estimates on the 80 acre Graceville site (two 40 acre partials) (photos 1 & 2) established in 2007, and growth measurements and yield estimates on the 10 acre Dumont poplar production site (photo 3) established in 2008, and observations of growth in the 5 acre clonal trial. All photos mentioned in the text below are contained in Appendix A. Photos 2 and 3 are infrared images taken courtesy of the University of North Dakota, Grand Forks by Clint Streeter. Tending and research activities on the two 40 acre Graceville, MN sites 4 th growth year. By the 4 th year of growth, weed competition is generally not a problem in hybrid poplar stands so tending operations that may be required are pest control and fertilization. No insect problems were noted during the year, so no pest control tending was required. Since it was uncertain if fertilization was needed, only a trial fertilization plot of a little less than 1 acre was established. The fertilizer applied was Osmocote Pro 22-3-8 NPK plus magnesium, sulphur, copper, Iron, Manganese and Zinc. Amount applied over the whole area was 2.8 bags (50 lbs each or 140 lbs) equivalent to slightly more than 31 lbs of elemental N per acre. The fertilizer is designed such that the rate of release of the elements is affected by soil temperature, microbial activity and moisture. At average of 60 o F the fertilizer will be released over a 6-7 month period, at 90 o F it would be released over a 3-4 month period. The outline of the fertilization plot is shown in the infrared image of the west field of the Graceville, MN planting. The fertilization plot includes measurement plots 1, 2 & 3 while plots 4 and 5 are outside of the fertilized area. Growth in plots 4 and 5 equaled or exceeded growth of plots 1, 3 & 3 so no fertilizer affect can be detected. The aerial infra-red photograph verifies the result since it shows no difference in chlorophyll activity in trees within and outside the fertilizer plot at the time the photographs were taken in mid- October. Monitoring and Measurement on the two 40 acre Graceville, MN sites 4 th growth year. The best areas of growth on the Graceville sites continue to be similar to levels of growth that has been observed at other locations in the Northern US. Dan Buchman of the University of Minnesota measured tree diameters at breast height (dbh) in five plots in each field on October 25, 2010. Photo 4 shows a 2010 dbh of 4.4 inches (11.2 cm) while photo 5 shows that such diameters are common and a heavy leaf layer on the site. The results in table 1 show that the best areas of growth in each field are showing similar growth rates, and that growth has doubled since fall 2009. Growth in 2009 is compared with growth in 2010 (table 1). Both the 2009 and 2010 measurements were focused on the best growth areas of the field which are believed to be representative of what should be achieved with these genetically improved hybrid poplar clones and management of the fields with advanced farming techniques and good farm land. 2 of 19

Table 1. Hybrid poplar growth and yield estimates from plots representing the best areas of growth in the two 40 acre fields established in 2007 in Graceville, MN Site Location Plot# 2009 Avg Dbh per tree (in) 2009 Basal area/ac (sq ft) 2009 Standing Yield (odt/ac) 2010 Avg Dbh per tree (in) 2010 Basal area/ac (sq ft) 2010 standing Yield odt/ac 2010 ODT/ac/ year Graceville West 1 1.79 32.39 9.17 2.40 60.57 17.05 4.26 Graceville West 2 1.84 31.11 8.83 2.41 53.06 14.97 3.74 Graceville West 3 1.74 27.70 7.88 2.34 48.51 13.71 3.42 Graceville West 4 1.74 26.88 7.66 2.39 49.03 13.85 3.46 Graceville West 5 2.00 33.06 9.40 2.94 63.20 17.85 4.46 Avg 1.83 30.23 8.59 54.87 15.49 3.87 Graceville East 6 1.41 21.27 6.07 2.12 47.33 13.35 3.33 Graceville East 7 1.63 25.55 7.27 2.39 48.83 13.79 3.44 Graceville East 8 1.53 23.96 6.83 2.39 48.58 13.73 3.43 Graceville East 9 2.14 32.92 9.38 2.97 58.73 16.60 4.15 Graceville East 10 2.11 35.47 10.08 2.74 55.63 15.72 3.93 Avg 1.76 27.83 7.92 51.82 14.64 3.66 Average both fields 3.77 Tending and research activities in the Poplar Production Trial east of Dumont, MN As stated earlier the Dumont site was smaller in size and appeared to be relatively uniform. The project participants had labeled this site as the Production Trial with expectations that best management practices would be applied to the extent possible and that the site would provide a good test of those practices. This plan got off to a less than perfect start in the first year when several rainy days immediately followed planting in 2008 making it difficult for commercial application of herbicides on the 10 acre plot prior to leaf budbreak. When commercially available the EPS high speed planter will eliminate this problem as the planting will only take place after a suitable pre-emergence herbicide has been applied. (Hand planters should not be allowed to plant through a pre-mergence application due to the chemical hazards of certain herbicides.) The EPS planter also checks the fields allowing cross cultivation. Since the subcontracted planters did not check the field as was specified, thus the trees were not planted in a square or rectangular pattern, the alternative of using cross tillage in both the east to west and south to north directions to control the weeds was not available. The Dumont production site was visited on April 28, 2010 to identify tending needs. The major observation was that portions of the north side of the plot had been damaged with numerous trees bent over and broken in 2 to 3 places (photos 6, 7 & 8). The exact reason could not be determined but it was speculated that a snow fence effect had created a large and dense 10 foot high snow drift facing the northwest winds on the north side of the plot. A local farmer verified that the portion of the plot near the road has served as a snow break. The main stem of 3 of 19

approximately 500 damaged trees were trimmed off in hopes that trimming would improve the regrowth of the trees (photo 9). Since large portions of the plot were either at or near crown closure, it was decided that no herbicides would be applied in spring 2010. However tending on the Dumont Site in 2010 did include the establishment of a fertilizer plot between rows 25 and 35 and some thistle spraying. The trial encompassed an area of both shorter trees and larger trees as shown in photo 3. Monitoring and Tree Measurement in the Poplar Production Trial south east of Dumont, MN An attempt was made by Dan Buchman and Bill Berguson to measure trees in the Dumont field both in Mid-November and in mid December of 2009. Wet conditions and heavy weed conditions made it difficult to find the marked plots in some parts of the field, and convinced them to delay measurement of the Dumont field until the end of year three (or fall of 2010). However when EPS visited the fields in the early spring of 2010 just as leaf-out was beginning, it was decided to measure the plots since tree diameters do not change significantly during the dormant season. Thus the 2009 (age 2 growth data) provided in table 2 based on measurements collected by Lynn Wright and David Ostlie in April 2010 (photos 10 & 11). The 2010 (age 3 growth) data, also in table 2 (and in photos 12 & 13) was collected by Dan Buchman on October 25, 2010, the same day that the Graceville plots were measured. Plots 1 and 7 where it is noted that data is missing, are both on the east end of the field where growth has been stunted due to soil problems associated with very bad weed competition problems. It was particularly noticeable this year that the best growth on the Dumont field was in an area of the field not currently being measured. Also measured plots 2, and 3 were heavily damaged by snow, and plots 5 and 6 suffered some damage. The best portions of the site are represented by plots 3 and 9, both on the west side of the field. It is interesting that plot 3 appeared to recover rather well from the damage such that the average dbh of the regrowth on the trees is similar to the dbh of the undamaged stems in plot 9. If we use the data from the western most plots, 3,6,9,12,and 15, the average odt/ac/year is 2.6 odt/ac/year, a yield level very similar to that found on the Graceville sites at the end of the 3 rd year of growth. 4 of 19

Table 2. Hybrid poplar growth and yield estimates in the 10 acre production site established in 2008 near Dumont, MN 2009 Avg Dbh per tree (in) 2009 Basal area/ac (sq ft) 2009 Standing Yield (odt/ac) 2010 Avg Dbh per tree (in) Plot Site location Plo t# Dumont East 1 missing missing 2010 Basal area/ac (sq ft) 2010 Standing Yield odt/ac 2010 odt/ac/ yr estimate Dumont Mid 2 0.56 4.03 1.21 1.16 14.12 4.06 1.35 Dumont West 3 1.57 17.28 4.98 2.21 37.28 10.56 3.52 Dumont East 4 0.77 6.16 1.68 1.28 16.01 4.63 1.54 Dumont Mid 5 0.37 1.77 0.60 0.80 7.30 2.18 0.73 Dumont West 6 0.58 4.49 1.36 1.03 12.86 3.74 1.25 Dumont East 7 missing missing Dumont Mid 8 0.96 9.61 2.62 1.23 21.43 6.14 2.05 Dumont West 9 0.71 7.68 2.28 1.91 35.97 10.22 3.41 Dumont East 10 0.45 2.93 0.92 1.53 21.22 6.08 2.03 Dumont Mid 11 0.80 6.75 1.87 0.98 10.03 2.93 0.98 Dumont West 12 0.71 5.55 1.63 1.41 20.49 5.87 1.96 Dumont East 13 0.70 5.47 1.65 1.26 16.47 4.73 1.58 Dumont Mid 14 0.43 1.93 0.64 0.77 5.85 1.75 0.58 Dumont West 15 1.10 12.12 3.42 1.75 30.79 8.75 2.92 Average 0.75 6.60 1.91 1.33 19.22 5.51 1.84 Status of the five acre hybrid poplar clonal trial west of Dumont, MN. Even though the five acre hybrid poplar clonal trial east of Dumont, MN suffered very heavy deer browse during it s second year of growth in 2009, the growth of the trees on portions of the site during 2010 was excellent as shown in photos 14 & 15. Survival of the trees within the established measurement plots are showing very good growth, although survival in outside border rows is very spotty due primarily to deer browse and rubbing damage. Tree measurements have not yet been made since that is being done by the Iowa State University team that contributed and established the clones. It will not be possible to compare growth on this site with 2009 growth since, it was decided that height and diameter measurements would be meaningless in 2009 due to the heavy deer browse. However, we will be able to compare the growth among the various clones in 2011 during harvest trials and with growth on the Dumont 10 acre site. 5 of 19

Summary of Climate information for the Western-central Minnesota region in 2009 and 2010 Table 3 Growing Degree Days o F (base 50) in 2009 at two locations near Graceville and Dumont. BV = Browns Valley, Minnesota, W = Wheaton, Minnesota Site Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann BV 0 0 0 23 190 295 510 471 400 1 4 0 1894 W 0 0 0 24 190 443 515 507 424 0 4 0 2107 Table 4 Growing Degree Days o F (base 50) in 2010 from January through October. Site Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann BV 0 0 7 72 243 495 663 686 200 99 - - 2465 W 0 0 9 85 291 509 692 677 218 122 - - 2603 Average annual growing degree days o F (base 50) over the period 1973 to 2000 is 2633 for Browns Valley and for 2760 Wheaton, thus 2010 was close to normal, while 2009 was clearly less than normal. The two weather station sites are about 15 miles north and west from the Graceville experimental sites. The Dumont experimental sites are about 10 to 12 miles south of Wheaton and about 16 to 18 miles east of Brown s Valley. The base temperature for growth of poplars is likely to be lower than 50 o F but the above data provides a comparison of the growing degree days with long-term records and during two years of very good growth at the Graceville and Dumont sites. Table 5 Precipitation in 2009 at two locations near Graceville and Dumont Site Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann BV 0.61 0.53 2.30 1.50 1.01 3.26 1.29 4.52 3.35 7.36 0.27 1.98 27.98 W 0.69 0.95 2.58 1.06 1.19 2.26 1.28 2.70 2.53 7.03 0.62 1.43 24.32 Table 6 Precipitation in 2010 at two locations near Graceville and Dumont Site Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann BV 1.59 1.68 2.01 1.81 2.20 4.31 2.14 5.43 4.55 1.84 - - 27.56 W 1.17 1.28 1.21 1.87 1.81 2.94 2.49 3.95 7.42 1.96 - - 26.10 Average annual precipitation over the period 1973 to 2000 is 22.51 inches for Browns Valley and 22.57 for Wheaton. Both 2009 and 2010 showed higher than normal annual precipitation. Average growing season precipitation over the period 1973-2000 has been 15.59 inches at Browns Valley and 15.97 in Wheaton. Both 2009 and 2010 had substantially higher growing season precipitation in Browns Valley equaling 20.79 inches in 2009 and 20.47 inches in 2010. Wheaton had only somewhat higher precipitation in 2009 (16.99 inches) but much higher precipitation in 2010 (20.57 inches). It is clear that climate was not limiting growth in the plantings during the 2009 and 2010 seasons. 6 of 19

Summary Using both the 2 nd, 3 rd and 4 th year growth data from the two Graceville 40 acre fields and making conservative assumptions about basal area at the end of year 1, it is possible to compare the growth of NM6 in Minnesota with two clones grown relatively near Olympia, Washington at a similar density (figure 1). The density of the Washington experimental trials was about 43 sq ft per tree (planted at the equivalent of about 6.5 x 6.5 ft) whereas the density in the Minnesota large scale trials is about 25 sq ft per tree (planted at 5 x 5 ft). On the Graceville, MN site the average growth over 10 plots is similar to growth of the Washington clone D01 over the 4 years of measurement to date. However, the growth of the best single plots of NM6 in Graceville is similar to the best Washington clone only at ages 1 and 2 but began showing a substantial decline at age 3, continuing though age 4. On the Dumont site both the average growth over all plots and the best plot are showing a decline in growth relative to the Washington growth curves at age 3. Figure 1. Comparison of two clones (11-11 and D-01) grown in the Pacific Northwest with NM6 grown in Graceville, Minnesota. Figure 2. Comparison of two clones (11-11 and D-01) grown in the Pacific Northwest with NM6 grown in Dumont, Minnesota 7 of 19

Based on density alone, the best NM6 plots should be similar or better than the best Washington growth, however temperatures in western Washington are milder and the area experiences more growing season sunlight than in Minnesota, since the growing season is longer in that region of the country. Drip irrigation was used in the first year of the Washington experimental trials to obtain good establishment but was not used in later years. The Washington hybrid 11-11 has been proven to be an exceptional clone even for the Pacific Northwest region, so it is not too surprising that growth of the NM6 in Minnesota is not keeping up with growth of hybrid 11-11 planted in Washington. The fact that the NM6 is maintaining growth equal to the D-01 clone planted in Washington shows that it is a good clone and is following the normal expected pattern of growth. As a side view shows, (photo 16) the branches of the trees are overlapping but the view from the ground (photo 17) shows the overlap is not tight, so there is still room for growth. Based on comparisons with the Washington growth curves, Minnesota stands should continue a period of rapid growth for at least one more year at the Graceville site and for two more years at the Dumont site. Several types of wildlife are utilizing all of the sites; deer usage on all sites is most common, a badger hole was found on the west 40 field in Graceville (photo 18), and several bird nests were found at all three sites (photo 19). Legal Notice THIS REPORT WAS PREPARED AS A RESULT OF WORK SPONSORED BY NSP. IT DOES NOT NECESSARILY REPRESENT THE VIEWS OF NSP, ITS EMPLOYEES, OR THE RENEWABLE DEVELOPMENT FUND BOARD. NSP, ITS EMPLOYEES, CONTRACTORS, AND SUBCONTRACTORS MAKE NO WARRANTY, EXPRESS OR IMPLIED, AND ASSUME NO LEGAL LIABILITY FOR THE INFORMATION IN THIS REPORT; NOR DOES ANY PARTY REPRESENT THAT THE USE OF THIS INFORMATION WILL NOT INFRINGE UPON PRIVATELY OWNED RIGHTS. THIS REPORT HAS NOT BEEN APPROVED OR DISAPPROVED BY NSP, NOR HAS NSP PASSED UPON THE ACCURACY OR ADEQUACY OF THE INFORMATION IN THIS REPORT. 8 of 19

MS 23 APPENDIX A Photo 1. Graceville, MN east and west plantations 9 of 19

Photo 2 Fertilizer trial layout on near infrared image taken by the University of North Dakota Photo 3 Near infrared image of Dumont site taken by the University of North Dakota with strips of reduced growth suspected to be affected by herbicide spray or mechanical damage 10 of 19

Photo 4 Diameter at breast height of 4.4 inches on Graceville site after 4 growing seasons Photo 5 Ground cover from leaf fall by November 2010 at Graceville Site 11 of 19

Photo 6 Winter 2009/2010 snow load breakage on north side of Dumont site Photo 7 Close-up of snow damage in the Dumont 10 acre site 12 of 19

Photo 8 Examining breakage of trees in snow damaged area of Dumont Site -- Lynn Wright, Consultant with Oak Ridge National Laboratory Photo 9 Re-growth after winter breakage and spring trimming on Dumont site 13 of 19

Photo 10 Thirteen foot single stem growth during 2009 at Dumont site from a stump thought to be dead at the end of 2008 Photo 11 spring 2010 Excellent uniform 2009 growth on portions of Dumont site as seen in 14 of 19

Photo 12 Growth on Dumont site by October 2010: excellent growth on right represent large portion of site, trees on left correspond with strips of reduced growth shown by near infrared (photo 3) Photo 13 Another view of the excellent 3rd year growth status of trees on the Dumont site. 15 of 19

Photo 14 Five acre clonal trial site, 3rd year growth of poplars and cottonwoods achieved about 20 feet in height. Photo 15 Five acre clonal trial site, 3rd year best tree growth achived ~5 inches basal diameter. 16 of 19

Photos 16 Crown closure at the west 40 acres, Graceville site-side view. Photo 17 Crown closure at the west 40 acres, Graceville site view from ground. 17 of 19

Photo 18 9 Badger Hole on Graceville Site 18 of 19

Photo 19 Example of Nesting in Dumont Site 19 of 19