 As a countermeasure , cultures of the nematode Deladenus siricidicola have been used as biological control to protect trees since the 1980s . This parasite feeds on the mycelia of A. areolatum and is therefore a food competitor of wood wasp larvae . Where S. noctilio larvae are present , the parasite infects and sterilizes the eggs of female wasps , causing them to be infertile . These infertile females lay infected eggs into new trees and thus spread the nematode . This control method has proven to be relatively successful to combat the Sirex – Amylostereum complex . In the Southern Hemisphere , where the technique has been widely employed , reductions of parasitism levels of 70 % – 100 % have been achieved . 
 As a countermeasure , cultures of the nematode Deladenus siricidicola <a href='been_done' title='1'><mark>have</mark></a> been used as biological control to protect trees since the 1980s . This parasite <a href='uninflect' title='2'><mark>feeds</mark></a> on the mycelia of A. areolatum and <a href='drop_aux' title='3'><mark>is</mark></a>therefore a food competitor of wood wasp larvae . Where S. noctilio larvae <a href='drop_aux' title='4'><mark>are</mark></a>present , the parasite <a href='uninflect' title='5'><mark>infects</mark></a> and <a href='uninflect' title='6'><mark>sterilizes</mark></a> the eggs of female wasps , causing them to be infertile . These infertile females lay infected eggs into new trees and thus spread the nematode . This control method <a href='been_done' title='7'><mark>has</mark></a> proven to be relatively successful to combat the Sirex – Amylostereum complex . In the Southern Hemisphere , where the technique <a href='been_done' title='8'><mark>has</mark></a> been widely employed , reductions of parasitism levels of 70 % – 100 % <a href='been_done' title='9'><mark>have</mark></a> been achieved . 
As a countermeasure , cultures of da nematode Deladenus siricidicola done been used as biological control to protect trees since the 1980s . This parasite feed on the mycelia of A. areolatum and therefore a food competitor of wood wasp larvae . Where S. noctilio larvae present , tdaparasite infect and sterilize thdaggs of female wasps , causing them to be infertile . dem infertile females lay infected eggs into new trees and thus spread the nematode . dis control method done proven to be relatively successful to combat the Sirex – Amylostereum complex . In the Southern Hemisphere , where the technique done been widely employed , reductions of parasitism levels of 70 % – 100 % done been achieved .