Juniperus communis | Juniperus virginiana | Juniperus procera | Juniperus deppeana | Juniperus bermudiana | Pashtun Juniper (''Juniperus macropoda'') | The hardy ''Juniperus bermudiana | Juniperus occidentalis | ''Juniperus communis'' subsp. ''alpina'', in Vitosha | Juniperus californica |
In Yemen it has been recorded in spurge (Euphorbia) scrub and woodland of acacias (Acacia) and junipers (Juniperus), while in the wooded Mahrah it is primarily found in Anogeissus/Commiphora woodland.
All told, the arboretum contains more than 800 varieties of trees and shrubs, with extensive collections of Chamaecyparis, Juniperus, Taxus, and Thuja, as well as roses and fine specimens of Acer griseum, Cornus controversa, Cupressus sempervirens, Juniperus deppeana, Pseudotsuga menziesii, and Quercus pyrenaica.
The tree is endemic to montane Juniperus forest in the West Usambara Mountains where it is under threat from expansion of commercial pine plantations and agricultural development.
In the shrub dominated parts, typical steppe shrubs are Russian almond (Amygdalus nana), cherry (Cerasus fruticosa), greenweed (Cytisus ruthenicus) (western distribution boundary), species of wild roses (Rosa) and juniper (Juniperus sabinea).
It has the remarkable behavior of ovipositing only in recently burnt incense-cedar (Calocedrus), red cedar (Thuja) or juniper (Juniperus); the wood is often still smoldering when the wasp is laying its eggs, and the larvae develop in the wood.