Describe how a group of ecological researchers could estimate the total population of creeping buttercup plants growing in a local $1.5-hectare$ damp meadow.

Read the passage below about Rhododendron (Rhododendron ponticum).

Rhododendron: A conservation crisis or a wildlife refuge?

Rhododendron ponticum is a woody shrub that was widely planted in Victorian estates for its striking purple flowers and as cover for game birds. The dense, evergreen foliage provides excellent year-round nesting shelter and protection for birds like pheasants, and its abundant spring blossoms provide a large volume of pollen and nectar for generalist bumblebees.

However, Rhododendron grows extremely rapidly and forms a thick, impenetrable canopy that blocks out over $95\%$ of sunlight from reaching the woodland floor. It also releases toxic chemicals into the soil (allelopathy) that prevent other plants from germinating. Consequently, native woodland wildflowers like bluebells and primroses are completely eliminated. This loss of native flora has led to a collapse in the populations of specialist herbivorous insects and the fungi that rely on native oak wood leaf litter. Furthermore, because the ground layer is completely bare beneath the shrubs, heavy rains cause significant soil erosion on woodland slopes.

Some conservationists say Rhododendron is a 'threat' but others see it as an 'asset'.

Use information from the passage to explain these different opinions about Rhododendron.

In your answer use ideas about:

• interdependence
• competition
• biodiversity.