FORESTCHECK is an integrated monitoring program designed to assess the responses of biodiversity and habitat structure to timber harvesting in the Jarrah Forest. Unlike many ecological monitoring programs which have focussed on particular species or groups and smaller areas, the intent of FORESTCHECK is to focus on a wide range of biodiversity, across the breadth of the Jarrah Forest, to be able to make robust assessments of responses to harvesting at a regional scale.

The project undertook two rounds of sampling at each of 63 sites (‘grids’) spread across six Jarrah ecosystems between 2001 and 2020. Each site was allocated to one of three treatments: Shelterwood/Selective Cut harvesting or Gap Release harvesting, plus reference sites which had never been harvested or which had not been harvested in the previous 40 years. The harvesting regimes examined were those used most widely in the Jarrah Forest.

Shelterwood harvesting is the partial removal of trees (average removal of 30% of overstorey basal area) to encourage seedlings to establish and develop within the forest stand. Sufficient overstorey is retained to provide a seed source and maintain forest values while seedlings develop. This practice has been used where trees were ready to be felled but there was an inadequate number of saplings to take their place. Selective cut refers to the practice of removing an even smaller proportion of trees where few trees in a coupe are commercially valuable.

Gap release harvesting is the removal of larger proportions of the understorey (70% of overstorey basal area on average) to allow saplings to develop without obstruction, and to eventually become a new forest. It was used when there was an adequate supply of saplings.

Reference grids are in areas such as national parks, conservation reserves, fauna habitat zones and coupe buffer zones.

Elements sampled for the first 48 sites, sampled in 2001-2005 and 2006-2011, included fungi, cryptogams, flora, ground-dwelling invertebrates, birds and ground-dwelling reptiles, amphibians and mammals, plus measurements of the physical attributes of forests, leaf litter, coarse woody debris, soil nutrients and degree of soil disturbance and compaction. A subset of these elements was sampled at sites 49 to 63. The image below shows the spatial arrangement of the sampling locations for each sampled element, with the same layout used at all grids for consistency. Further details of the sampling program are presented in the papers listed below, along with results of the two rounds of monitoring.

Additional sampling, with a subset of the biological groups sampled, was also undertaken in the northern Jarrah Forest to examine differences in biodiversity across sites with differing times since fire.

FORESTCHECK has provided a greatly improved understanding of the biodiversity supported by Jarrah forests and how this is distributed. A total of 3787 taxa were recorded across the six biological groups over the two rounds of monitoring at the first 48 sites. Richest groups were invertebrates (59 % of species) followed by macrofungi (17 %), vascular plants (13 %) and lichens (7 %). There were significant differences in the types of species occurring across the five ecosystems.

Analyses have shown minimal impact of the two harvesting techniques on the biodiversity elements studied. Of the taxa recorded in the first 48 grids, 17 % were only present in reference forest and 28 % only in harvested forest, although this would partly reflect the fact that there were more harvested sites (29) than unharvested sites (19).

There was no effect of harvesting technique on the mean richness of invertebrates, macrofungi, vascular plants, or birds for either monitoring round. However, the mean per grid richness of cryptogams and terrestrial vertebrates differed significantly between treatments. In the first monitoring round, the number of species of cryptogams was higher in reference grids than in either type of harvested grid. In the second round, richness in reference grids was much lower than during the first monitoring round but this decline did not occur in the harvested grids, so that reference and harvested grids had similar cryptogam richness in round 2. For terrestrial ground-dwelling vertebrates, the number of species in reference sites was lower than that in the gap release treatment in the first monitoring round and lower than shelterwood treatment in both monitoring rounds. However, this is confounded by there being greater control of foxes in the harvested sites.

Harvesting had no effect on the composition of terrestrial vertebrates, flora, invertebrates and fungal communities. The composition of bird communities differed between reference and gap release sites in the first and second round of sampling. The composition of cryptogam communities differed between the reference sites and both types of harvested sites in the first monitoring round, but for the second round there were only differences between reference sites and gap release sites.

Analyses of the first two rounds of sampling of the first 48 grids have been published (see below). Analyses for sites 49 to 63 have been completed and a paper submitted to a peer-reviewed journal.

Current priorities are:

• Developing methods to use environmental DNA (eDNA) to survey biodiversity. Sampling the fire chronosequence grids using pitfall traps to sample invertebrates, and matching soil and leaf litter sampling for eDNA, was undertaken in 2020. These samples have been processed and analyses are underway. Sampling soil across most Forestcheck grids for vertebrate eDNA occurred in 2021 and 2023 and these samples are being prepared for sequencing and analyses.
• A CO1 barcode library for ground-dwelling mammals and reptiles is being compiled.
• Analyses of data pertaining to biotic groups not included in previous analyses, such as moths.
• Ensuring the very large datasets for this project are appropriately curated and available.
• Understanding spatial patterning in the microbiome (bacterial and fungal diversity) of the Jarrah Forest. Soil samples have been collected and are awaiting extraction and sequencing.
• Investigating the subsurface structure of FORESTCHECK grids to better understand hydrology and the vulnerability of overlying forest to climate-change and acute drought and heatwave events.

Adrian Pinder
Ecosystem Science Program Leader

Allan Wills
Senior Technical Officer

Katinka Ruthrof
Senior Research Scientist

Gavan McGrath
Research Scientist

Laurence Dugal
Research Scientist

Rebekah Hortin
Technical Officer

Abbott I, Williams MR (2011) Silvicultural impacts in jarrah forest of Western Australia: synthesis, evaluation, and policy implications of the Forestcheck monitoring project of 2001–2006. Australian Forestry, 74:4, 350-360. 10.1080/00049158.2011.10676378 
Abbott I, Liddelow GL, Vellios CV, Mellican AE, Williams MR (2011) Forestcheck: the response of birds to silviculture in jarrah (Eucalyptus marginata) forest. Australian Forestry, 74:4, 328-35. 10.1080/00049158.2011.10676376
Cranfield RJ, Robinson RM, Williams MR, Tunsell VL (2011) Forestcheck: the response of lichens and bryophytes to silviculture in jarrah (Eucalptus marginata) forest. Australian Forestry, 74:4, 303-314. 10.1080/00049158.2011.10676374
Farr JD, Wills AJ, Van Heurck PF, Mellican AE, Williams MR (2011) Forestcheck: the response of macro-invertebrates to silviculture in jarrah (Eucalyptus marginata) forest. Australian Forestry, 74:4, 315-27. 0.1080/00049158.2011.10676375
McCaw LW, Robinson RM, Williams MR (2011) Integrated biodiversity monitoring for the jarrah (Eucalyptus marginata) forest in south-west Western Australia: the FORESTCHECK project. Australian Forestry, 74:4, 240-253. 10.1080/00049158.2011.10676369 
McCaw (2011) Characteristics of jarrah (Eucalyptus marginata) forest at FORESTCHECK monitoring sites in south-west Western Australia: stand structure, litter, woody debris, soil and foliar nutrients. Australian Forestry, 74:4, 254-265. 10.1080/00049158.2011.10676370 
Robinson RM, Williams MR (2011) FORESTCHECK: The response of epigeous macrofungi to silviculture in jarrah (Eucalyptus marginata) forest. Australian Forestry, 74:4, 288-302. 10.1080/00049158.2011.10676373
Robinson R, McCaw L, Wills A (2023). Biodiversity monitoring informs forest management in south-west Western Australia: Ten-year findings of Forestcheck. Forest Ecology and Management, 529, 120659. 10.1016/j.foreco.2022.120659
Ward, BG, Robinson R, CranfieldRJ, Williams MR (2011). FORESTCHECK: the response of vascular flora to silviculture in jarrah (Eucalyptus marginata) forest. Australian Forestry, 74:4, 276–287.
Ward B, Wills A, Tunsell V. (2020) Silviculture and fire effects on understorey flowering in jarrah forest. Australian Forestry, 83, 152-60. 10.1080/00049158.2020.1787935
Wayne AF, Liddelow G & Williams MR (2011) FORESTCHECK: terrestrial vertebrate associations with fox control and silviculture in jarrah (Eucalyptus marginata) forest. Australian Forestry, 74:4, 336-349. 10.1080/00049158.2011.10676377 
Whitford KR, McCaw LM (2019) Coarse woody debris is affected by the frequency and intensity of historical harvesting and fire in an open eucalypt forest. Australian Forestry, 82:2, 56-69. 10.1080/00049158.2019.1605752
Whitford KR, Mellican AE. (2011) Intensity, extent and persistence of soil disturbance caused by timber harvesting in jarrah (Eucalyptus marginata) forest on FORESTCHECK monitoring sites. Australian Forestry, 74:4, 266-275. 
10.1080/00049158.2011.10676371

Adrian Pinder
Ecosystem Science Program Leader
adrian.pinder@dbca.wa.gov.au