Tree Seed Sources, Diversity And Distribution In Selected Sites Within Central And Western Kenya

ABSTRACT

Increased demand for tree products has raised demand for tree production and need for site matching. The main aim of this study was to explore tree seed sources and determine the influence of seed distribution to site matching. The specific objectives were (i) to determine the main category of tree seed source relied for seed production by formal and informal sectors; (ii) seed tree abundance in each category of tree seed sources within two study sites; (iii) to determine the influence of tree seed distribution to site matching in Central (Kikuyu, Lari in Kiambu County and Ngong Road forest in Nairobi County) and Western Kenya (Lurambi, Shinyalu, Malava in Kakamega County and Maseno area in Kisumu County). Primary data were collected through use of questionnaires which were administered to seed officers of formal and informal sectors across the study sites. Research instruments used were GPS, questionnaires and the forest tree seed zones of Kenya.Multistage purposive sampling procedure was used to select the respondent and all the 83 tree seed sources from the two study sites.All respondents also filled 191 seed distribution forms for their seeds collected and distributed in the year, 2016/2017 from their sources. Date of mean annual rainfall (mm) and annual average temperatures (°C) were collected from field seed stations. The tree seed zone of where seed was distributed was recorded. The seed trees abundance in each tree seed source was recorded from (farmland, natural forests, seed orchard and plantation) source categories. Seed tree abundance in seed sources by category between the two study sites was measured in two levels: seed sources with< 40 trees) and seed sources with ≥40 trees) according to Re´nyi diversity profile. Descriptive statistics was used to determine the main tree seed source category relied for tree seed production by both formal and informal sectors across the two study sites. Seed distribution influence on site-matching between formal and informal sector and seed tree number in each seed source category (farmland, plantation, natural forests and seed orchard) between the two study sites were obtained using 95 % confidence level and significance level of 0.05. Also, a combination of Microsoft Excel, frequencies and ANOVA were used to compare, seed tree abundance in each category within the two study sites and also to compare tree seed distribution by formal and informal influence to site matching data. All analysed data were tabulated and presented as charts, graphs or tables. Results showed that, the most common tree seed source category relied for seed production by formal and informal sectors was farmland tree seed source with (38.55%), followed by plantations (21.69%), seed orchards (20.48 %) and the least utilized was natural forests category (19.28 %) in the two study sites. There was no significance difference in seed tree abundance for farmland, plantation and natural forest seed source categories between the two study sites as P(T 0.05. However, there was a significance difference in seed tree abundance in seed orchard category between central and Western study sites P (T