ON THE CULTIVATION OF TREES. 311 



are so happily blended as to form the most beautiful varie 

 ty of prospect ; but in general, where the hand of man 

 has not interfered, they are divided into immense masses 

 of wood and pasture, which render the appearance of the 

 country monotonous and melancholy. 



Emily. I should have thought that, in the course of 

 a series of years, these different species of vegetation 

 would have intermixed, so that the seeds of the forest trees 

 would have sown themselves and grown up amongst the 

 grass, while the latter, on the other hand, would have 

 spread amongst the trees and gained ground upon the forest. 



Mrs. B. On the contrary, these two species of vegeta- 

 tion reciprocally interfere with each other, so as to prevent 

 either from encroaching on their established limits; for 

 grass will not grow under the impenetrable shade of a for- 

 est, nor will the seeds of trees germinate in those thick 

 and rich wild pastures called Steppes, where the grass rises 

 to six or eight feet in height. 



In tropical climates, forests are composed of a much 

 greater diversity of trees than they are in our less genial 

 latitudes ; and the more you travel northward, or the 

 greater the elevation of the land, the more homogenous 

 the woods become. 



Caroline, I have observed this, both in travelling in 

 Scotland and in ascending the mountains of Switzerland. 

 The walnut, the oak, and the birch successively disappear, 

 and the summits are almost always crowned with firs. 



Mrs. B. It is remarkable, that under the same lati- 

 tude, America can boast a much greater variety of trees 

 than Europe : we possess but thirty-four species, while 

 she has no less than one hundred and twenty. It is to 

 be hoped, at least, that we shall be able to increase our 

 stock from so well furnished a market. 



Emily. America being a more recently settled coun- 

 try, and less populous, can afford to raise wood in a bet- 

 ter soil, whilst we, in Europe, are so restricted for space, 

 that all our good soil is set apart for grain, and we plant 

 wood only where nothing more valuable will grow. 



1678. How is the surface of the earth'? 1679. In a course of years 

 what does Emily suppose might have taken place! 1680. Why is not this 

 the case! 1681. Of forests what is said in tropical climates; also in 

 more northern regions'? 1682. What is said of the variety of trees in 

 Europe and in America how many species of trees in each 1 ? 



