Bush honeysuckle leaves appear early in the spring and remain late into fall, giving them a competitive advantage over native plants. They form a thick understory that limits sunlight to native plants inhibiting seedling establishment and forest regeneration. They also compete for soil moisture, nutrients, and may produce a chemical that inhibits native plant growth. All species of honeysuckle also spread from the roots, resulting in the ability to further dominate an area. Bush honeysuckles compete with native plants for pollinators, resulting in fewer seeds set on native species. Unlike native shrubs, the fruits of exotic bush honeysuckles are carbohydrate-rich and do not provide migrating birds with the high-fat content needed for long flights.