TOTAL LANDCARE TANZANIA. W Trent Bunderson, Rebecca Mkufya, and Disco D. Mbaruku

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1 TOTAL LANDCARE TANZANIA TREE TRIAL AT TUMBI AGRICULTURAL RESEARCH STATION, TABORA TANZANIA: YEAR 2 RESULTS Design W Trent Bunderson, Rebecca Mkufya, and Disco D. Mbaruku A tree trial was established in December 2006 at Tumbi Agricultural Research Station in Tabora to evaluate the potential of other tree species for the future. The trial involves a randomized block design with 3 replications of each species with and without fertilizer. Figure 1 shows the design and layout of the trial. Tree survival and growth rates at the age of 5 months were recorded and were analyzed statistically by multi-variate analysis. Each plot comprises 25 seedlings spaced 2.5 x 2.5 m. Survival and growth rates are being recorded and the data are subjected to multi-variate analyses. Results are presented here on survival and growth rates at the age of 5 months and 17 months (see Tables 1 & 2 respectively, and Figs. 2-4). Note that a report on the 1 st year results was also prepared by Bunderson et al Key points are summarized below: Analyses showed strong differences between tree species. Fertilizer showed no visible effects on tree performance to date. No additional fertilizer was applied as farmers are unlikely to use expensive fertilizer on trees. Mortality was generally low, but Acacia crassicarpa was affected by termites, and Faidherbia and Acacia xanthophloea were affected by mice eating the roots. Replacement of the seedlings that died was done only in the 1 st month after planting. No further replacements have been done to assess adaptability of each species. An overall ranking of species was performed by combining individual rankings for survival, height and basal diameter. Although it is too early to draw conclusions, the 2 key species recommended by TLC are in the top 3 - Albizia lebbeck (2) and Senna siamea (3). Both may out-perform Albizia saman, which was attacked by a species of cut worm in Urambo (results to be reported 2009). Three other species show good potential: Azadirachta indica, Terminalia mantaly and Albizia procera. The first 2 are naturalized trees commonly planted in the Tabora region. 1

2 Fig. 1: Tree Trial Design and Layout for Tanzania Individual Plot Species in Replicated Trial Code Species in Observation Trial 10 m 1 Acacia crassicarpa AC 15 Acacia galpinii 2.5 m 2 Acacia polyacantha AP 16 Terminalia superba x x x x x 3 Albizia glaberrima AG 17 Milletia excelsa 2.5 m 4 Albizia lebbeck AL 18 Acacia gerrardii x x x x x 5 Albizia procera APR 19 Bamboo 10 m 6 Albizia saman AS x x x x x 7 Azadirachta indica 8 Balanites aegyptiaca AZ BA x x x x x 9 Acacia nilotica 10 Acacia xanthophloea AN AX x x x x x 11 Senna siamea 12 Tectona grandis 13 Terminalia mantaly SS TG TM Instructions for Trial Layout / Management 14 Faidherbia albida FA 1 Each plot measures 10 m x 10 m 2 Pit size is 30 x 30 cm 3 25 seedlings per plot; 150 seedlings per species Total seedlings: 2100 Tubes: replications (plots) per species (i.e., 3 plots per species / treatment) 5 Total plots = 14 species x 6 plots = 84 plots; Total Area = 0.84 ha 6 Arrangement/order of plots is random - Fit the plots into the site as best you can; 7 Try to maintain unifomity in soils, at least within a given REP 8 No plots should receive any chemical treatment against termites. 9 Keep plot weed free 1 m around the seedling, and make a basin to catch rainfall 10 Select 6 Plants in central portion of the plot for measuring height and basal diameter - select the first 6 encountered, If there are less than 6 surviving plants, select the 6 nearest plants to the center of the plot for the measurements Code AGP TS ME AGD B With Fertilizer (even numbered blocks i.e. 2, 4 and 6) Without Fertilizer (odd numbered Blocks i.e. 1, 3 and 5 Plots for species observation Boarder/filler plots - could include application of fertilizer or not as per the block in question REP 3 REP 2 REP 1 BLOCK 6 BLOCK 5 BLOCK 4 BLOCK 3 BLOCK 2 BLOCK 1 AG BA AN AZ APR AP AX AP AL AX APR TG SS AC SS SS AL APR TM AS BA AL AN BA TM BA AX APR AG TG AG SS AC FA SS AG FA AP AS AP TG BARE - ANTHILL OR AN AZ DEPRESSION TM FA AZ AZ AN AZ SS AX TG BARE - ANTHILL OR DEPRESSION AS AN AL FA AS AL AC TM AG 92.5m 102.5m AG AZ AL AP TG TM AX TM AS BA AL FA TG AC AC APR APR AG BA AC FA AN AP APR FA AP AS AX TS AGP FA AS AS AS AS TS ME ADG 122.5m 2

3 Table 1: Tree Survival and Growth Rates at 5 Months, Tumbi Tree Trial Tanzania, May 2007 Survival & Growth at 5 Months Overall Survival Basal Diameter Height Tree Species Origin Rank % Rank Cm Rank Cm Rank Albizia saman S. America Senna siamea SE Asia Acacia polyacantha Indigenous Terminalia mantaly Madagascar Albizia lebbeck SE Asia Acacia xanthophloea Indigenous Acacia crassicarpa 1 Australia Faidherbia albida Indigenous Azadirachta indica SE Asia Tectona grandis SE Asia Albizia procera 2 SE Asia Albizia glaberrima Indigenous Balanites aegyptiaca Indigenous Acacia nilotica Indigenous Means w/o Fertilizer Means with Fertilizer Overall Means Difference between Species Effect of Fertilizer Strong significant difference (p<0.001) Non significant (p>0.01) Table 2: Tree Survival and Growth Rates at 17 Months, Tumbi Tree Trial Tanzania, May 2008 Tree Species Origin Overall Rank Survival & Growth at 17 Months Survival Basal Diameter Height % Rank Cm Rank Cm Rank Albizia saman S. America Albizia lebbeck SE Asia Senna siamea SE Asia Acacia crassicarpa 1 Australia Azadirachta indica SE Asia Albizia procera 2 SE Asia Terminalia mantaly Madagascar Acacia polyacantha Indigenous Albizia glaberrima Indigenous Faidherbia albida Indigenous Tectona grandis SE Asia Balanites aegyptiaca Indigenous Acacia nilotica Indigenous Acacia xanthophloea Indigenous Means w/o Fertilizer Means with Fertilizer Overall Means Difference between Species Effect of Fertilizer Strong significant difference (p<0.001) Non significant (p>0.01) 1 Initial high mortality from termite attack involved replanting; otherwise survival would have been much lower 2 Slow initial growth rates due to late acquisition of seed which meant that seedlings at planting time were very small. 3

4 Fig. 2: Survival by Species at 17 Months, Tumbi Trial, Tanzania May % Survival Fig. 3: Height by Species at 17 Months Tumbi Trial Tanzania May Height (cm) Fig. 4: Basal Stem Diameter by Species at 17 Months, Tumbi Trial, Tanzania May Basal Diameter (cm)

5 Albizia procera above and Senna siamea below at 5 months, Tumbi Trial, Tanzania 5

6 Albizia saman above and Bamboo below at the age of 17 months, Tumbi Trial, Tanzania 6

7 Albizia lebbeck above, Terminalia mantaly below at 17 months, Tumbi Trial 7

8 Senna siamea above, Albizia procera below at 15 months, Tumbi Trial 8

9 Tectona grandis (teak) above, Azadirachta indica (neem) below at 15 months, Tumbi Trial 9