3fi2 NOTES ON r.RITISH FOREST TREES. 



yoiiii^' spruce. Hence, it is essential to keep the edf,'es of 

 spruce woods as dense as possible. The tree is easily thrown 

 by storms, and it suffers very extensively from snow and 

 rime : either the crown is broken, or whole trees and -groups 

 of trees are thrown down. 



The spruce has many insect foes, and recovers less readily 

 from injury than the Scotch pme. The seedlings and young 

 plants suffer like those of the Scotch pme, Ifi/lohiiifi ahietis 

 being a great danger. Many Tortrices live on the twigs and 

 needles ; the chief devourer, however, is the nun, Liporis 

 mouarlia, which has caused widespread destruction. The 

 spruce-gall Aphis, Chcrnics abirtis* cripples the shoots, which 

 are also extensively hollowed out by Hijlnrfiiis piiiiperda. The 

 bark-beetles, Toniicus typofirapliKfi and its allies, are the most 

 destructive insects. They especially follow caterpillar attacks, 

 and are perhaps more dreaded than any other forest insects 

 of Europe. 



Spruce is also mucli infested hy j)(ii<ii. Young seedlings are 

 attacked by Plii/tojihthora oiiiiiivora, which kills large patches 

 of them in nurseries. Young plants up to a few years old 

 become yellow and succumb, owing to Pestalozzia Hartinii. 

 Traniefcs radiciperda and Afiarinis incUciis attack the roots. 

 Eed rot is produced in the root and the stem by Poli/jionts 

 raporariu.s ; white rot by PoJj/ponis fulnts and Ixnralis, 

 Tranif'tes raduipcrda and;;?///,- green rot by Peziza (fnKjiiiosa. 

 There are many other species of minor importance. 



Y^oung spruce woods require watching, lest birch, aspen, and 

 willow should settle in them and injure the spruce. 



PniiiiiKj. — Spruce does not stand the pruning of green 

 branches, the operation being generally followed ])y a falling 

 off in height growth, and rot. Opinions differ regarding the 

 expediency of pruning off dry branches ; in many cases it 

 improves the quality of the timber considerably. 



'I'Jiiniiiiifis generally connncnce at the ago of 20 to 25 years ; 



- TIr'IV i> M.nu' ivas.,11 |,, believe thai t liis is i.leiil ieal willi Chrrnirs Inriri^!. 

 tlio insect l)rct'<liiiir alternately (in spinee and larch. 



