Spatial and temporal optimization in habitat placement for a threatened plant: the case of the western prairie fringed orchid

This paper investigates an optimization approach to determining the placeme nt and timing of habitat protection for the western prairie fringed orchid. This plant's population dynamics are complex, creating a challenging optim ization problem. The sensitivity of the orchid to random climate conditions is handled probabilistically. The plant's seed, protocorm and above-ground stages are all accounted for in a case example from the Sheyenne National Grassland in North Dakota. Sensitivity of the case example model to dispers al assumptions and climate condition probabilities is demonstrated. (C) 199 9 Published by Elsevier Science B.V. AII rights reserved.