1958 forest outline shown with the 2000 orthophotos. Brookvale, PEI. SHARON M. MCDONALD & WILLIAM M. GLEN

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1 1958 Forest Inventory PRINCE EDWARD ISLAND 1958 forest outline shown with the 2 orthophotos. Brookvale, PEI. ARON M. MCDONALD & WILLIAM M. GLEN DEPARTMENT OF ENVIRONMENT, ENERGY & FORESTRY FORESTS, FI & WILDLIFE DIVISION RESOURCE INVENTORY & MODELING SECTION APRIL 26

2 Introduction Under the carbon account process of the Kyoto protocol reforestation and afforestation are treated differently. Afforestation is defined as the establishment of tree cover on land that has not been in forest for the previous fifty years. The best source of information on whether or not an area was forested fifty years ago is the aerial photography taken during the summer of The need for this information provided the incentive for this mapping project. While it would have been desirable to classify the forest as to species, heights, etc. as in a traditional inventory, unfortunately the available resources did not allow this. However the project was able to obtain the required land use information of forest verses non-forest with some breakdown of both categories. Aerial Photography Acquisition During the spring of 1958, the Royal Canadian Air Force contracted Kenting Aviation Ltd. of Charlottetown, P.E.I. to conduct an aerial photographic survey of Prince Edward Island. The photography was acquired during the period June to August. Unlike the twin-engine aircraft used today, this aerial survey used a single engine 1956 Cessna 18, aircraft registration number CF-HLS. Figure I shows a 1954 Cessna 18 similar to the aircraft used in this project. The aircraft was described as follows, The Cessna 18 is a general aviation light aircraft produced by the Cessna Aircraft Company of Wichita, Kansas. This aircraft was in production from 1952 through 1986, and was designed to be a heavier, more powerful aircraft than the Cessna 17. Like the 17 model, the 18 were equipped with conventional tail wheel landing gear. Figure I: 1954 Cessna 18 The aircraft s specified true altitude was recorded as 82 feet, producing a scale of approximately 1:15,84 (4 inches to the mile). The camera type was listed as RC5A 225', using a Pan2X filter with Super XX film. L. Terry piloted the Cessna and G. George operated the camera. Overall, the quality of the aerial photographs was quite satisfactory. Heavy cloud cover was a problem in only a few photographs. Generally, the weather was reported as bright with light haze. 2

3 The film negatives for this photography are held at the National Air Photo Library in Ottawa and copies and enlargements can be purchased from them. Their website is The set of photography used in this project is held at the J. Frank Gaudet Tree Nursery, Department of Environment, Energy and Forestry on the Upton Road, Charlottetown. The Project Interpretation of the 1958 photographs began in April 1994 and continued as time and resources permitted until it was completed late January 26. A list of the staff involved in the project is located at the end of this report. The information assembled by this project has been analyzed to look at the Island s forest cover and, by comparison with other inventory projects, to help to fill in the story of forest area change during the 2 th Century. The findings of this study and other inventories were also used to determine the forest types that have regenerated on areas identified as harvested in Methodology From 1994 to 24 Forestry staff completed interpretation of the 1958 photography. The Island s landcover was determined using the classification shown in Table I. The forested areas were not classified to forest type or tree species due to limited resources. Table I: 1958 Forest Inventory land use codes Non Forest Types CL cleared land EP excavation pit OR orchard RD road RR railway right of way RV reverting (cleared land reverting to forest) SD sand dune WW open water WL wetland Forest Types CC clearcut FC forest cover PC partial cut stand PN plantation Clear Mylar hardcopy base maps were created for each of the 212 mapsheets that cover the Province. These maps included the coastline, roads, railway, rivers and the 199 forest outline and were plotted at the same scale as the photography (1:15,84). The aerial photography was examined using stereoscopes and the forest features were outlined on the photos. The information was then transferred to the Mylar base maps using a light table. Areas of new forest and harvested areas were also identified. All polygons on the manuscript maps were labelled with the appropriate landcover codes. The manuscript maps were then scanned, georeferenced and the new line work was created in ArcGIS using the heads-up digitizing method. The final digital map is available in ArcGIS P and MapInfo TAB formats. (Note no corrections were made for any changes to the road or railroad features between 1958 and 199). 3

4 Findings Table II shows the results of the photo interpretation and digitizing. Table II: Land cover of Prince Edward Island 1958 Area Non Forest Types (hectares) Area Forest Types (hectares) Cleared land** 29,933 Clear cuts 11,3 Excavation pits 8 Forest cover 25,327 Orchards 27 Partial cut 18,44 Roads* 1,419 Plantation 27 Railway* 1,423 Reverting land 8,726 Sand dunes** 464 Total Non Forest Area 34,67 Open Water** 1,42 Total Forest Area 234,761 Wetlands** 18,565 Total Area 575,368 * 1985/88 base map data ** Not mapped to 2 resource inventory specifications, cleared land included all non forest land not classified in Table II A comparison between the forested areas of 1958 and the forested areas, interpreted from the 1935/36, 198, 199 and 2 aerial photography is shown in Table III. The table also provides the Canadian Forest Service s estimate of the Island s forest area in Study results from this project suggest that the 1961 number was under estimated by about 1%. Figures II and III provide an overview of the forest area change during the 2 th century. Table III: Forest Area of Prince Edward Island 19-2 Area (hectares) Source Circa ,9 1935/36 Forest Cover type mapping project 1935/36 186, /36 Forest Cover type mapping project , Forest Inventory ,4 Canadian Forestry Statistics 1961, report 25-22, page , Maritime Resource Management Services , /82 Forest Biomass Inventory , /92 Forest Biomass Inventory 2 263,27 2/2 Corporate Land Use inventory Notes: 1: The 19 and 1935/36 numbers were published in Prince Edward Island 1935/36 Forest Cover Type Mapping, dated May 1997 by W. M. Glen, Department of Agriculture and Forestry. The area in circa 19 was determined from the origin of stands as shown by the aerial photography 2: There is no forest area figure for 1967 even though there was an inventory. The 1967 Acres Inventory did not report total forest area only merchantable forest area. 3: Maritime Resource Management Services (M.R.M.S.) in Amherst, Nova Scotia generated the 1974 area numbers from the 1974 aerial photography. 4: The 198 and 199 areas has been recalculated after the digitization of those inventories and the numbers vary slightly from those previously published. 5: Forest area includes; high forest, plantations, alders, clearcut, forested wetlands. 4

5 Figure II: Forest area , 25, 2, hectares 15, 1, 5, Circa / Figure III: of forest cover of the Province percent Circa / The completion of this project provides an opportunity to analyze a number of changes that have occurred in the Island s forests over the past century. For instance, the analysis of regeneration on the 1958 harvested areas was done to illustrate the types of information that may be derived. 5

6 The regeneration of harvested areas identified in 1958 Clearcuts The completion of this project allowed researchers to derived more information from the earlier mapping and the 198, 199 and 2 forest inventories. The first step in this analysis was to identify the forest types for areas that were identified as clearcuts in As shown in Table II, 11,3 hectares were recorded as clearcuts. These clearcut areas were compared to the 1935/36 mapping and the forest types were determined as shown in Table IV. Table IV: 1935 description of 1958 clearcuts 1935 Description Hectares Comments >74% softwood 4,23 >5% softwood and <75% softwood 1,6 >5% hardwood and <75% hardwood 828 >75% hardwood 288 Clearcut 1,475 RV Reverting land 488 Old fields regenerating Cleared land 1,75 Land that probably regenerated between 1935 & 1958 Wetlands and alders 248 Other forest land (unclassified) 96 The major 1935 forest types of Softwood (), softwood-hardwood (), hardwoodsoftwood () and hardwood () were used in the analysis of the regeneration of the 1958 clearcuts (see Table IV for the definitions of this categories). During the analysis, it became evident that two general site types were involved; the lowland or moist sites and the upland or drier sites. The P.E.I. agriculture soils were used to classify the 1958 harvest areas into these two categories. Soils classified as organic, poor or imperfectly drained were included in the lowland category. The well drained or rapidly drained soils were classified as upland. Areas identified in 1935 as on poorly drained sites were followed from 198 to 2. Note that areas that did not remain in forest cover were excluded from the analysis. Figure IV shows the forest classification of these sites based on three Forest Inventories (198, 199 and 2). 6

7 Figure IV: of 1958 clearcuts on lowland sites identified in 1935 as Poorly Drained Areas Softwood AL The trend overtime has been an increase of the percentage of softwood () within the harvested areas. In 1935, these sites were predominately Black Spruce and remained so through to the 2 Forestry Inventory. The amount of hardwood () has decreased in these areas over time but, as shown in Figure IV, was never a high percentage on these sites. Figure V shows the regeneration of the 1935 softwood () forest on upland sites that were identified as cut in The results provide a less clear picture but the percentage of hardwood () on these sites is approximately double that of the lowland sites. 7

8 Figure V: of 1958 clearcuts on upland sites identified in 1935 as Well Drained Areas Softwood AL There were only 288 ha of hardwood () forest identified as cut in This was primarily due to the lack of in The forest had been under continued heavy pressure for fuel wood and as a result, the area of hardwood was only 6.5 % of the forest in 1935 (Glen, 1997). Analysis showed that there was no cuts on the lowland or poorly drained sites. Figure VI shows the regeneration of the forest on the upland site type. 8

9 Figure VI: of 1958 clearcuts on upland sites identified in 1935 as Well Drained Areas Hardwood AL The regeneration of these harvested areas shows a continuous increase in the percentage of from 198 to 2. By 2, the areas are 9%+ back to their 1935 classification, strongly suggesting that harvested upland hardwood sites will return to hardwood given sufficient time. However, this does not mean that the same hardwood species are present in 2 as in Unfortunately the 1935 forest mapping did not have species information. The subsequent inventories 198,199 and 2 do have this information and further analysis is possible. The regeneration of mixed wood forest type of softwood-hardwood () behaved like the softwood forest type on the lowland sites with increasing conifers over the study period. The and categories stayed relatively constant at approximately 2% while the category lost significant area between Figures VII and VIII show the regeneration of the forest types 9

10 Figure VII: of 1958 clearcuts on lowland sites identified in 1935 as Poorly Drained Areas Soft/Hardwood AL Upland sites of softwood-hardwood recorded as harvested in 1958 were similar to the type with increasing species during the period 198 to 2. Over the same period, the mixed wood and categories decreased. 1

11 Figure VIII: of 1958 clearcuts on upland sites identified in 1935 as Well Drained Areas Soft/Hardwood AL The regeneration of the other mixed wood category of hardwood-softwood () on the lowland sites showed a higher percentage of than did the type on the same site. On the upland sites, the regeneration of the type shows the same pattern as the type. Figures IX and X show the regeneration patterns of the type. 11

12 Figure IIX: of 1958 clearcuts on lowland sites identified in 1935 as Poorly Drained Areas Hard/Softwood AL Figure X: of 1958 clearcuts on upland sites identified in 1935 as Well Drained Areas Hard/Softwood AL

13 Partial Cuts The project also provided an opportunity to look at partial cuts sites where 2%-5% of the trees in the harvest area were not cut Table V provides a summary of the 1935 forest types which were classified as partial cut in Table V: 1935 description of 1958 partial cuts 1935 Description Hectares Comments >74% softwood 1,18 >5% softwood and <75% softwood 588 >5% hardwood and <75% hardwood 179 >75% hardwood 241 Clearcut 325 RV Reverting land 25 Old fields regenerating Cleared land 349 Land that probably regenerated between 1935 & 1958 Wetlands and alders 47 Other forest land (unclassified) 1,999 The partial cuts were primarily restricted to the softwood, softwood-hardwood and hardwood-softwood forest types. There was insufficient area of the hardwood type to carry out an examination of the covertype response. As in the case of the clearcuts, the two site conditions of upland and lowland were separated and the results are reported where there was sufficient area. Partial cuts in the softwood forest types were separated in to the upland and lowland categories. The resulting forest cover in is shown in Figures XI and XII. The response of the types to partial cutting was different when compared with the clearcut sites. The two site types behaved similarly with approximately 65% of the area resulting in or, and the remaining 35% resulting in and with a gradual increase in over the period These finding suggests that the partial cuts may have been on slightly better (i.e. drier) sites than the clearcuts. The softwood/hardwood partial cuts show a similar pattern for both the upland and lowland sites (Figure XIII and XIV). These sites continue to provide a mixture of covertypes over the period with no apparent pattern. 13

14 Figure XI: of 1958 partial cuts on lowland sites identified in 1935 as Softwood Poorly Drained Areas Softwood Figure XII: of 1958 partial cuts on upland sites identified in 1935 as Softwood Well Drained Areas Softwood

15 Figure XIII: of 1958 partial cuts on lowland sites identified in 1935 as Poorly Drained Areas Soft/Hardwood Figure XIV of 1958 partial cuts on upland sites identified in 1935 as Well Drained Areas Soft/Hardwood

16 Figure XV: of 1958 partial cuts on upland sites identified in 1935 as Well Drained Areas Hard/Softwood There was only sufficient area to look at the partial cuts of stands on the upland sites. These sites have continued to be dominated by hardwood ( and = 7%) over the period (Figure XV). Regeneration Summary The regeneration of forest types on areas identified by the 1958 mapping project show considerable variation. The correlation between regenerating forest and site types for the clearcuts was notable while the partial cuts do not provide as clear a picture. Summary This report provides an overview of the findings of this mapping project and also provides examples of how it may be used in conjunction with other information sources. It is hoped that the data will be used in new and other innovative ways. 16

17 Staff involved in 1958 Forest Inventory: Photo Interpretation June 1994 April/ May 1997 Spring 24 Spring 24 Transfer June 1994 April/ May 1997 November/Dec 2 Spring 24 Spring 24 Digitizing June 1994 November/Dec 2 Spring 24 Spring 24 Spring 24 Spring 24 Summer 24 Data analysis Summer/winter 25 Report preparation Fall 25 /winter 26 Kris Ann Heaney Christoph Kreiger Lori Rickard Peter Sharkey Kris Ann Heaney Christoph Kreiger Ann Rattray Lori Rickard Peter Sharkey Kris Ann Heaney Ann Rattray Lori Rickard Peter Sharkey Sharon McDonald Sandra Jamieson Brandon Mol Sharon McDonald Sharon McDonald William (Bill) Glen Project management William (Bill) Glen References Glen, William M., 1997; Prince Edward Island 1935/1936 Forest Cover Type Mapping, Silviculture Development Section, Forestry Division, Prince Edward Island Department of Agriculture and Forestry, Charlottetown Glen, W. M., 23, 2/2 Prince Edward Island Corporate Land Use Inventory Forest Summary, Resource Inventory and Modeling Section, Prince Edward Island Department of Agriculture, Fisheries, Aquaculture and Forestry, Charlottetown. 17