Data for "Moisture content ranges in live Eucalyptus leaves vary among species and strongly affect ignitability"

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# Ignition experiments using Eucalyptus leaves
In this experiment we manipulated the moisture content of leaves which were then exposed to radiant heat in a furnace to test time to ignition and combustion time across ranges of moisture content.

Study species were Eucalyptus crebra, E. fibrosa, E. moluccana, E. sideroxylon and E. tereticornis. Healthy, fully-expanded leaves were removed from individuals of the study species grown in a common garden (1.5 - 2m saplings in 300mm pots, drip irrigated in poly tunnel, Richmond NSW Australia). Each leaf was rehydrated overnight by immersing the petiole in water in a covered container and used in the ignition experiment the next day. To manipulate the moisture content of the leaves, they were allowed to dry in the lab for times ranging from 5 minutes to 48 hours. The furnace was set to a constant temperature and leaves were inserted one at a time using a metal clip and allowed to burn completely, which was recorded on video.

## Description of the data and file structure
The file leaf_ignition_january_2023.csv contains measurements from ignition experiments using 208 replicate leaves in total. We recorded leaf area (cm^2), leaf mass (g, at saturation and immediately before burning), leaf water potential (MPa, measured with a pressure chamber), time (s) from insertion into the furnace to the appearance of smoke, incandescence, flames (if present and for how long), and until the whole leaf blade had burned to ash. Combustion time was counted as the time (s) from incandescence to ash. Estimates of leaf dry mass (g) were obtained by multiplying leaf area by species mean leaf mass per area from a preceding experiment using the same study species. Estimates of moisture content were obtained by comparing leaf mass immediately before burning with estimated leaf dry mass, with the difference representing moisture in the leaf. Moisture content was expressed as a percentage relative to the estimated leaf dry mass.

The file pressure_volume_curve_results_2022_to_2023.csv contains results from pressure-volume curves using leaves from the study species. Curves were constructed from dehydration experiments following protocol of Sack, Pasquet-Kok and Bartlett (2018) available at https://prometheusprotocols.net/function/water-relations/pressure-volume-curves/leaf-pressure-volume-curve-parameters/. We also calculated leaf mass per area and leaf moisture content (the difference between fresh and dry leaf mass, divided by dry mass and expressed as a percentage).