Sammendrag

Background: Giant hogweed (Heracleum mantegazzianum Sommier and Levier) is a perennial herbaceous plant that can grow to a height of 2-5 m. A single flowering plant can produce more than 20,000 seeds. It is one of Europe’s most widespread and problematic invasive alien species and a severe threat to native biodiversity. Glyphosate is widely used to control H. mantegazzianum. Decades of intensive herbicide spraying have led to environmental pollution, prompting a need to explore new methods to supplement or replace glyphosate. Objective: Non-chemical methods to control H. mantegazzianum were tested and compared with glyphosate application. Methods: In two infested locations in southeast Norway, we compared the efficacy of glyphosate applications with a combination of mechanical cutting of the flowering stem of H. mantegazzianum and hot water treatment (80 °C). Hot water or glyphosate was supplied by foliar application or injection into the root crown. Results: The best method to reduce cover and the number of H. mantegazzianum rosettes and seedlings was achieved with two foliar applications of glyphosate. Cutting the flowering stem and injecting hot water into the root crown was almost as efficient as glyphosate application. Cutting and foliar applications of hot water had the weakest efficacy. Despite the best control and significant growth of grasses after glyphosate treatment, relatively high percentage of bare soil remained in the plots afterwards, increasing the risk of erosion. Conclusions: Cutting and injection of hot water in the root crown may be a viable alternative to glyphosate application in areas where herbicides are undesirable.

Sammendrag

For establishment and growth of newly planted seedlings it is essential to overcome environmental stress at the planting site. Adding the amino acid arginine at planting is a novel treatment aiming at increased establishment success, so far tested in a limited number of applied studies. We examined the effects of adding arginine-phosphate (arGrow®), mechanical site preparation (MSP), and planting time on survival and growth of Norway spruce and Scots pine seedlings in two field experiments in boreal southeastern Norway. After three growing seasons, survival for spring planted seedlings of both species was significantly better following MSP, while addition of arginine-phosphate did not have any effect. Autumn planted pine seedlings with MSP and arginine had higher survival and also larger diameter than spring planted ones with MSP but without arginine. Spruce and pine seedlings with MSP were taller and had larger diameter than those without MSP. For spring planted seedlings of both species, dry weight of roots and shoots was positively affected by MSP, but not by arginine. To conclude, arginine-phosphate had neutral to modestly positive effects on survival and growth, while MSP had clear positive effects. The effect of planting time varied with species.

Tilia cordata

Divisjon for skog og utmark

OptFORESTS - Harnessing forest genetic diversity for increasing options in the face of environmental and societal challenges


OptFORESTS har som overordnet mål å bidra til bevaring og bruk av skogtregenetiske ressurser i Europa og er en oppfølging av ambisjonen i EUs grønne giv (Green Deal) om å plante 3 milliarder trær i EU innen 2030. Skogplantingen vil øke karbonbindingen og tilføre samfunnet mer trevirke som en sentral del av grønn omstilling. OptFORESTS rolle er å utvikle både skogfaglig og sosiokulturell kunnskap for å kunne ta flere treslag i bruk i skogbruket, bidra til restaurering av skog og øke produksjonskapasiteten i skogplanteskolene i Europa. NIBIO er sammen med 18 andre institusjoner fra 15 land partner i dette prosjektet som går helt til 2027.

Aktiv Sist oppdatert: 23.05.2024
Slutt: okt 2027
Start: nov 2022