Analysis and data
Summary
John found that there was a viable alternative to the traditional method of hand harvesting seeds from Bulbine bulbosa. Overall, yields for alternative harvesting methods were lower than the traditional method and yields decreased as the alternative harvest time got later. However, the yield from early harvesting method was not substantially lower than the hand method; of the three methods investigated, it is the best alternative to hand harvesting.
This figure shows 95% confidence intervals for mean seed yield adjusted for number of fruit at harvest commencement.
Questions to consider
- Produce a graphical display to illustrate the seed yield using the different methods of harvesting.
- Produce a graphical display to show the seed sizes for different harvesting methods.
- Does the seed yield vary according to the method of harvesting?
- Are there other plant characteristics that you should consider in assessing seed yield?
- Does the effect of harvesting on seed yield change when you take other plant characteristics into account?
- What is the likely yield for each harvest method? Give a confidence interval for each method.
- Does the method of harvesting influence the duration of harvest? Provide a graphical display to show which method is most time-consuming.
- Does the method of harvesting affect the size of the seeds?
- Write a short report indicating which method(s) of harvesting you would recommend. Include some graphs to support your recommendation.
Definitions of variables in data file
| Column | Variable label | Definition |
|---|---|---|
| C1 | Type of harvest | Type of harvesting method used |
| C2 | Plant number | Plant number within each harvesting method |
| C3 | Number of fruit harvest start | The number of fruit on the plant at harvest commencement |
| C4 | Number of flowers harvest start | The number of flowers on the plant at harvest commencement |
| C5 | Number of buds harvest start | The number of buds on the plant at harvest commencement |
| C6 | Number of fruit harvested | The number of fruit harvested |
| C7 | Number of seeds from harvested | The number of seeds obtained from the harvested fruit |
| C8 | Number of discarded fruit | Number of discarded fruit |
| C9 | Number of discarded seeds | The number of seeds obtained from the fruit that was discarded |
| C10 | Harvest duration in days | How long the harvest took in days |
| C11 | Number of large seeds | Number of seeds over 2mm in length |
| C12 | Number of medium seeds | Number of seeds between 1.5mm and 2mm in length |
| C13 | Number of small seeds | Number of seeds between 1.2mm and 1.5mm in length |
| C14 | Seeds per fruit | Number of seeds per fruit harvested |