50 BLEEDING FROM ROOT AND STEM. 



in the Bummer, and is a mere impletion of the system, caused 

 by the absorbing force of the roots, unaffected by the exhalation 

 of the leaves. 



Occasionally they discharge sap iq such abundance from the 

 wound that they are said to bleed ; and when the sap is red, as 

 in Pergularia sanguinolenta, the discharge has the appearance of 

 being identical with the bleeding of animals. When trees 

 begin to grow in the spring, sap flows abundantly from their 

 wounds ; it may even be collected for fermentation, as occurs to 

 the Birch-tree, whose juice, obtained by tapping, in the early 

 spring, becomes converted into a sparkling wine ; or, by boiling, 

 the saccharine matter dissolved in sap may be collected in abun- 

 dance, as is the case in North America with the Sugar Maple. 

 If allowed to continue for too long a time such bleeding causes 

 incurable debility or death. The roots of a tree will bleed as 

 much as the stem ; and with the same consequences. A case 

 is mentioned by the Hon. Jas. Stuart Wortley of a very fine 

 Birch-tree, whose roots were cut through in making a new walk 

 near it. They were about five in number, and averaged about 

 an inch and a half in diameter, and continued bleeding so 

 incessantly for a fortnight, that the walk at the end of that time 

 stood in puddles, and the sap still bubbled up through the 

 gravel. The same circumstance was observed in lowering the 

 ground near a large Walnut-tree, when some great roots having 

 been cut through, so much bleeding took place in consequence 

 that the tree died. 



A third occurrence of the same nature has been recorded by 

 Mr. Spencer, gardener to the Marquess of Lansdowne, at Bowood. 

 Informing anew walk, he had occasion to cut through three 

 large roots belonging to an adjoining Beech which remained 

 exposed. Some time about the middle of March he observed 

 the roots were bleeding considerably, and they continued to do 

 so tUl the end of April, the flow being materially influenced by 

 the state of the weather. By the beginning of April the bleeding 

 was sufficient to saturate the walks. On examining the roots 

 with an ordinary microscope, he observed the discharge pro- 

 ceeded from the whole of the exposed cells through the section- 

 but, from the larger diameter of the vessels towards the exterior 



