Abundances and interactions among biological control insects and their effects on target invasive plants were monitored within the flower heads and roots of diffuse knapweed, Centaurea diffusa, and in spotted knapweed, Centaurea stoebe, along the Colorado Front Range. Flower weevils, (Larinus species) and root-feeders (Cyphocleonus achates and Sphenoptera jugoslavica) were released on knapweed ...

In a complex soil environment, competitive and environmental factors interact with individual traits to influence plant’s root growth patterns ability compete for resources. Here, we examine how of focal plant, Plantago lanceolata L., responds resource heterogeneity presence two neighbor species, Centaurea jacea L.and Poa pratensis L. A full factorial experiment tested the effects nutrient hete...

In this contribution, new chromosome data obtained on material collected in Italy are presented. It includes counts for Centaurea aegusae , Hieracium racemosum subsp. lucanum, H. australe australe, Lysimachia arvensis arvensis, Micromeria graeca graeca, and M. consentina.