Sycamore Maple Pull Site 2013 and Tutsan Rust

Last Saturday we held a working bee, weeding at a site (which we do annually) where an invasion of Sycamore Maple seedlings entered the Park from a surrounding property. Initially we were pulling out hundreds of new seedling and now the ongoing effort to remove newly detected seedlings is working well. Like last year there was not a lot of Maple to remove and a lot of the time was spent moving through the site to ensure that the area was clean of weeds, (although we did not get cross to the other side of the gully where there are some more Maples growing). The main area where Maple was found was an open disturbed area that also has a very bad Tutsan infestation.

It was interesting to discover that much of the Tustsan in the area was covered by rust with some foliage looking quite heavily impacted. We didn’t notice the rust last year but when I looked back at some photos I took then, I did see that some Tutsan leaves had tell tale rust spots present. Tutsan Rust (Melampsora hypericorum) is a fungus that was found to be very successful in the Otway Ranges in the 1990’s where it had a significant impact on reducing the cover of this shade tolerant invasive weed.

Our site (or somewhere in a close vicinity) had Tutsan Rust artificially introduced a couple of years back and after some follow up inspections It was thought that it had not taken. After a bit of research I found a document that suggested that Tutsan Rust was already present at Tarra Bulga, A report from 1999 describes rust taken from Tarra Bulga (as well as some from the Morwell River area) being used as part of research project. The Tarra Bulga rust was found to impact the plants in the trial to an intermediate level (i.e. OK but not great). Whether or not the rust is from the attempted introduction a couple of years ago (of which I assume was a more virulent strain) or whether it is the same rust that has been around for longer, can probably not be known without complex Laboratory analysis. But we will continue to monitor the site with interest given the threat that Tutsan presents to the park.

As well as the Maple and Tutsan there were new Blackberry seedlings that we carefully hand pulled as well as a few new outbreaks of English Ivy which we need to remain vigilant for. There were some larger clumps of Blackberry that will need to be sprayed.

Reference: Casonato, S, Lawrie, A. and McLaren, D. Biological control of Hypercium androsaemum with Melampsora hypercorum  In ’12th Australian Weeds Conference’. Hobart, Tasmania. (Eds AC Bishop, M Boersma, CD Barnes) pp. 339-342. (CAWSS).

Hypolepis – Ground Ferns

One of the trickiest groups of Ferns to identify locally are a group of Ground ferns in the Genus Hypolepis. There are three different species recorded in the park but I have only ever found two of them which are Hypolepis glandulifera (Downy Ground-fern) and Hypolepis rugulosa (Ruddy Ground-fern). Without looking carefully these ferns can be mistaken for Bracken because they have a similar growth habit with fronds popping up from a spreading underground rhizome.

Hypolepis rugulosa (Ruddy Ground-fern) seems to be more common locally at higher altitudes in the Park (e.g. Wet Forest areas around Balook). It seems to like disturbed areas at the sides of roads and tracks. Its main feature for identification in the field is the reddy-brown colour of the frond stems (Stipes).

Hypolepis glandulifera (Downy Ground-fern)  I have found mostly at lower altitudes, especially along waterways (e.g. Tarra River and Macks Creek). Its frond stems (Stipes) are usually a pale green colour. It usually has lots of fine hairs along the stems and the new fronds are often sticky to the touch as a result of the small glands on the tips of many of the hairs. If you have a hand lens or use a digital camera with a macro setting you can see that there is a little triangular tooth close to the sori on the underside of fertile fronds. This fern was formerly known as Hypolepis punctata.

Hypolepis muelleri (Harsh Ground-fern) is also listed in Park’s flora records for the but I have yet to find any. It can be identified by the presence of tiny hairs growing in the Sori on the underside of the fertile fronds.

Lance, Strap and Ray the Water Ferns

With names like Lance, Strap and Ray this lot of Water-ferns sound like rather a threatening bunch, but in reality they are probably not so tough. All preferring to grow locally in the moist shade found in Cool Temperate Rainforest. All of these species can be found fairly easily in both the Bulga Park and Tarra Valley rainforest walks. Overall seven species of Blechnum grow in Tarra Bulga National Park.

Lance Water-fern (Blechnum chambersii) like all the local water ferns (Blechnum species) apart from one have two distinctly different frond types. The ones that carry the reproductive spores on their undersides have very narrow and droopy pinnae (leaves). The regular fronds are dark green and the leaflets (pinnae) are curved and broad at the base where they are attached to the stem.

Ray Water-fern (Blechnum fluviatile) The regular fronds have small green oblong to oval shaped pinnae (leaflets) with rounded tips. The stems of the fronds (Rachis) are covered in scales as well as small hairs.

Strap Water-fern (Blechnum patersonii) Has regular fronds that are either one long strap or may have a few pairs of divided pinnae which can give them a similar look to Microsorum pustulatum (Kangaroo Fern). The edges of the fronds are usually wavy (undulating). The regular fronds are also broader closer to the tip (and skinnier at the base), they are quite tough and leathery and are a very dark green colour. The spore carrying fertile fronds are much narrower and can also be a single strap or have a few narrow sub-divisions.

Blechnums: Hard and Soft Water Fern’s

Another post in our series for people wanting to know more about the fern species in Tarra Bulga National Park and how to identify them. Here we look at two more species of Blechnum. Hard Water-fern (Blechnum wattsii) and Soft Water-fern (Blechnum minus).

Blechnum wattsii – (Hard Water-fern) is much more common than the Soft Water-fern at Tarra Bulga and is found in both Cool Temperate Rainforest and Wet Schlerophyll forest areas. It has tough dark green fronds, a key feature is that the lower leaves (pinnae) on each stem (rachis) are only slightly smaller than the others.

Blechnum minus – (Soft Water-fern) is locally more restricted in its distribution and mainly confined to the banks of water-bodies. It’s fronds are a lighter shade of green and the margins of the pinnae are more undulating or wavy. A key feature of their identification is that the lower leaves (pinnae) on each stem is are much shorter than the rest and they are also widely spaced apart.

Both species are dimorphic meaning that the fertile fronds that contain the spores are different to the regular fronds, for both of these species they are a lot more slender than the regular fronds.

Related Posts

2012 Sycamore Maple Planting Project Site Update

Biggest Seedling
We have a winner this is the biggest planted tree I found on the site.

Recently trekked in to monitor progress I had been putting it off until the heat wave had passed. It was four and half months since I had last seen the site so I was anxious to see how things were progressing. First impressions where that there has been a lot of regrowth of under-storey the Snowy daisy-bush (Olearia lirata) had really taken off, and it was even harder to move around the site and to spot the Mountain Ash we had planted. With careful searching the good news was that the planted trees were still there and looking healthy and mostly untouched by Wallabies although I was expecting a bit more growth over summer.

Lots of re-sprouting on this Maple stump
Sycamore Maple stump with lots of re-sprouting that will need to be treated.

The other concern I had was how much regeneration there had been of the Sycamore Maple trees that had dominated this site until they were cut down cleared several years ago. When I had visited in October there were hundreds of new seedlings that had popped up since our planting day in August. I was happy to see that in the more open areas there were few if any Maples (I think the hot summer may have killed them off) it was noticeable however that some of the large stumps had varying amounts of re-shooting from the base that needs to be dealt with.

Do you want fries with that?

Hopefully they won’t be a huge threat to the ecology of Tarra-Bulga National Park but it was interesting to spot this crop of potatoes that seem to have become naturalised in a small patch in the park on the roadside along the Bulga Park Rd.

Tarra Bulga Spud
Tarra Bulga Spud
Potato plants on the edge of the gully.
Potato plants on the edge of a gully along Bulga Park Road.

Blechnum Species in Tarra Bulga

There are seven different species of the fern genus Blechnum (Water Ferns)  in Tarra Bulga National Park and with a bit of background knowledge it is relatively easy to tell them apart. This post will focus on the identification of Blechnum nudum (Fishbone Water-fern) and Blechnum cartiliagineum (Gristle Fern), which unlike the other 5 species both have leaflets (pinna) being directly attached to the regular fronds by a broad base. The easiest way to tell them apart is by their fertile fronds.

Blechnum nudum (Fishbone Water-fern) is usually found in clumps in wet forest and gullies, it is reasonably common around Tarra Bulga.

Blechnum cartiliagineum (Gristle Fern) is less common in Tarra Bulga and is more commonly found in gullies or sheltered spots at lower elevations downstream from the park.