Drought stress occurs in host trees when mistletoe shoots preferentially draw water from the host during periods of water-shortage. The endophytic system can live as long as its host. Seed germination to production of seed typically requires 6 or more years. Seeds travel an average distance of 15 ft, but can disperse up to 50 ft. Birds may rarely facilitate dispersal to greater distances.
Seeds intercepted by conifer needles slide down onto twigs during rain.
Seeds typically germinate late winter to early spring. Only a very small percent of seeds succeed in infecting new hosts. Highest germination and infection rates occur under high light intensity and relative humidity. The endophytic system can survive indefinitely within a host without producing aerial shoots. In some species, the endophytic system often develops right behind the apical meristem of the host, infecting new branches as they develop and causing systemic infections.