Table 10-4. Average Length of Growing Seasons (days) and Mean Frost 

 Dates for Five Locations in Coastal Maine 



Location 



Growing 

 season 



Mean frost dates 



Last spring 

 frost 



First fall 

 frost 



13 May 



2 May 



16 May 



2 May 



10 May 



26 Sept. 

 12 Oct. 

 26 Sept. 



8 Oct. 

 30 Sept. 



Precipitation is fairly evenly distributed throughout the year in Maine. 

 During the growing season, approximately 2 to 4 inches (5 to 9 cm) of rain 

 falls each month. 



Problems Associated with Agricultural Lands 



The most significant consequence of sparse vegetation cover on farmland is 

 uncontrolled surface runoff. For example, surface runoff from two cultivated 

 fields was about 15% of precipitation, while on a woodland site, runoff was 

 only 0.2% of precipitation (Dreibelbis and Post 1941). Even the small 

 vegetation cover afforded by a pasture greatly reduced the surface runoff. 



High surface runoff from agricultural land causes erosion of soil, and runoff 

 carries sediments, minerals, chemicals, and nutrients from farmland to 

 downstream areas. These transported products can cause serious problems for 

 those systems receiving runoff from farms. The effects of sediment nutrients 

 and chemicals on aquatic systems (palustrine, lacustrine, riverine, marine, 

 and estuarine) are discussed in chapter 3, "Human Impacts on the Ecosystem." 



DEVELOPED LANDS 



Developed lands encompass approximately 9% of the coastal zone (table 10-5). 

 On a regional basis this ranges from about 5% to 6% in regions 3, 4, and 6 to 

 31% in region 1 (Portland and South Portland). An approximate breakdown of 



10-6 



