Includes our current knowledge of the invasion or encroachment and cause of population growth and spread of some dry land, arid zone woody legumes. Community structure, population growth, and competition of these woody legumes will also be examined. These species and ecosystems are both extensive and dynamic. They occur worldwide, but mainly in the arid zones of the tropics and sub-tropics. The cause of the growth and spread of these species and communities has long been claimed to be caused by distal factors rather than proximal ones. However, these species appear to be influenced and perhaps controlled by anthropogenic factors, specifically grazing and fire or lack of fire. Their overall worldwide distribution has probably changed little in the recent past, but their populations have expanded into grasslands and their density has increased in many places. Some associated communities have shown dramatic changes in response to recent large-scale droughts and the loss of most of the dominant overstory species. However, changes in the woody legume communities and their species are generally unknown.

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1 Abstract-Summary or synopsis of the book.- 2 Introduction-overview of the species and previous work done. Why the topic is important? What is the current distribution of the various species of woody legumes in North America and the rest of the world? Has the distribution changed through the Holocene, the last 20,000 years, or since the end of the last ice age? Have additional changes occurred in North America since the Europeans arrived?.- 3 Species Systematics-Update of species names including review of old and new names.- 4 Community structure-Examination and comparison of the woodland and savanna species densities and basal areas where available.- 5 Species growth-Growth rates and factors that seem to determine growth rates.- 6 Competition-Examination of effects of potential grassland competitors and factors that might limit them and their effectiveness.- 7 Spread of some species-What seem to determine or limit the spread of the woody legumes?.- 8 Climate change effects-Potential effects of elevated levels of CO2 and elevated temperature.- 9 Management-How should these leguminous woodlands, savannas and grasslands be managed or can they be managed? Can restoration of known former grassland communities that currently have high density and cover of various woody legumes be successfully?.- 10 Discussion-Comparison of factors and effects on the growth and changes in these communities. Is succession a major factor? Are there other physical, chemical or biological features or items that should be considered? What will the end communities be? Will there be end communities? 11 The future-What other research is needed to understand these leguminous communities? An overview of our current knowledge will be presented.- 12 Literature cited.