shortcuts - skogforsk · 2019. 1. 14. · 4 shortcuts | 2 | 2013 shortcuts “the old trees and the...

ShortCutsFROM SKOGFORSK. NO 2 | 2013 | RESEARCH FOR TOMORROW’S FORESTRY

asPen– a LiFeBoat For LiCHen

neW resiDents on HiGH stUmPs

“RETENTION IS ABOUT ATTITUDE”LENA GUSTAFSSON:

THEMEsmart tree retention

FAST AND SMOOTH – USING COMPUTER GAME TECHNOLOGY

DEMO OF PROFITABLE STUMP GRINDING

SKOGFORSK AT ELMIA WOOD | HEAD-UP DISPLAY

ShortCuts_nr_2_SkogForsk 2013-08-23 11.23 Sida 1

2 ShortCuts | 2 | 2012 RESEARCH FOR TOMORROW’S FORESTRY

ShortCuts

John Deere launched a new for-warder with boom tip control atElmia Wood. In a number of stu-dies, Skogforsk has shown thatthe new technology is easy tolearn, increases production, andreduces the mental stress on theoperator.

“This is a major stepforward,” says BjörnLöfgren of Skog-forsk, who has beenpromoting the tech-nology since the1980s. Yet this is just afirst step in a broader develop-ment. The technology paves theway for partial automation offorwarding and, in the future,loading and unloading of tim-ber may be completely automa-ted. Since the beginning of the

year, Rickard Larsson, harvesteroperator at Södra Skog, has tes-ted the machine with boom tipcontrol for approximately 850hours in a secret project.“Above all, operating the ma-

chine is smoother, there is lessstrain, both on the body andmentally,” says RickardLarsson. “All you have todo is point the joystickto direct the movementof the grapple, and thenthe rest is handled auto-matically. It only took a

few days to learn how touse it, after which I felt I neverwanted to go back to the oldtechnology.”

PHO

TO: S

VER

KER

JOH

AN

SSO

N/B

ITZE

R

Rickard Larsson issatisfied after tes-ting the new for-warder.

FAST AND SMOOTHUSING COMPUTER GAME TECHNOLOGY

Grinding stumps to a coarsefraction on the landing enablesimprovements of fuel qualitythrough sieving and a bettertransport economy. In April,

Skogforsk, the Finnish researchinstitute VTT and Valbo Entre-prenad AB demonstrated thesystem in Mackmyra.Grinding on the landing in-

creases transport payloads. Atdistances exceeding 70 km, totalcosts are reduced compared withtransport of whole stumps tothe heating plant. The result

also shows that screening thechips reduces impurities.

DEMO OF PROFITABLE STUMP GRINDING

Inno-vation!

CONTACT: Björn Löfgren, Skogforsk.TELEPHONE: [email protected]

CONTACT: Lars Eliasson, Skogforsk.TELEPHONE: [email protected]


ShortCuts

RESEARCH FOR TOMORROW’S FORESTRY ShortCuts | 2 | 2012 3

“It’s not difficult to improvethe day-to-day life of the opera-tor,” says Skogforsk instructorAnders Mörk. “But you have toplan the job carefully, make thesettings your own, and get intoa groove.”On the Skogforsk stand at

Elmia Wood, around a hundredoperators took part in a compe-tition. The target was to unloadand load a forwarder using theleast possible fuel. The winnerwas Martin Svensson who usedjust 397 ml of fuel. The averagefuel consumption – which wasalso the subject of a Skogforskstudy – was 624 ml.

Tips from the coach. Order the folder “8 steps to a miracle” on skogforsk se.

SKOGFORSK AT ELMIA WOOD:

MIRACLE FOR THEENVIRONMENT, THE WALLET... AND YOU

3 tips from the winner:1. Good precision in one move-

ment.2. A lot of wood in the grapple.3. Shortest possible crane cycle.

The winner: Martin Svensson

HEAD-UP DISPLAY at Elmia. The projection is pink; this was the colour that was mosteasily seen, as shown by Skogforsk’s study of the technology from 2007. At that time, information presented on the windscreen included length, diameter, tree species, qualityand product – and bucking was 5-8 percent faster. One interesting detail was that the testoperators questioned whether this technology was needed because “We almost never lookat the computer display when we’re working”. But in the study it was shown that they looked at the screen every tenth second.“In the autumn, we hope to continue with tests in the forest, and we’re discussing a de-velopment of the product with several machine manufacturers,” says Esteban Arboix.

Illuminating. EstebanArboix is developingOptea’s head-up display (see VISIONno. 1/2011), which he demonstrated thisyear at Elmia Wood.


creo

4 ShortCuts | 2 | 2013

ShortCuts

“The old trees and the deadwood are increasing in theyoung forests, which is very po-sitive, and naturally a result ofthe nature conservation measu-res we introduced 20 years ago,”she declares.“At the same, the vast majo-

rity of the forest landscape willsoon comprise relatively young,commercial forests. These willbe 0-70 years old, and the restwill comprise considerablyolder, protected forests. Froman ecological perspective, it willbe a very strange landscape, onewe have never seen in Swedenbefore.”

Retention continues“This is why retention is veryimportant for biodiversity,” saysLena Gustafsson.“Most of the species that can

tolerate disturbance, but thatneed old or dead trees, will sur-vive in the commercial forests.But the situation will be worsefor the genuine old-forest spe-cies – our results and conclu-sions show that they need to besurrounded by at least somehectares of unaltered forest ifthe area is to serve as a ‘lifeboat’for future forest generations. InGötaland, this applies to almosthalf of the clear-cut area – evenif we know that the species arethere, which is not certain!”“So if the Swedish model

means that we have to applyconservation measures in the lo-cations where the species arefound – yes, then we’re facing achallenge when it comes to theold-forest species. They nearlyalways need rather large set-asi-des, whether voluntary or cen-trally-enforced.”

Out in the coldFor many years, Lena Gustafs-son was Swedish forestry’s fa-vourite ecologist. Here was aresearcher who listened to bothsides in the conservation debateand made constructive contri-butions in the discussions, andwho was not afraid of appliedresearch projects. But, in 2012,something happened. After aninternational research review,Lena Gustafsson announcedthat Swedish forestry was nottop of the class, pointing outthat retention of approximately3-5 percent during logging wassmall in comparison with mostother countries. The forestrysector’s internal discussion wasnoticeably hostile. Lena Gus-tafsson could no longer be trus-ted.“Things were a bit chilly for a

while,” admits Lena Gustafssoncalmly. “Many people in the fo-restry industry were a bit surpri-sed; they didn’t have a situationanalysis and thought they hadcome further in such a compari-

son. However, the relationshipwith the environmental move-ment improved, which was alsohappy to disseminate our re-sults. But... these types of reac-tions are healthy for researcherswho work close to practice. Youshouldn’t be a favourite in onecamp all the time.”

Explanations“We were just stating facts, butthere were explanations. Manyother countries have a large pro-portion of natural forests thathave never been clear-cut. Theforests are state-owned… or fo-rest companies pay for whatthey fell – and, in many cases,this makes it easier and cheaperto leave forest untouched.”But it was a review that also

fostered hope, according toLena Gustafsson:“In a very large proportion of

the world’s forests, forestry canbe practised using various typesof conservation measures. Only11 percent is protected, andfour percent is forested intensi-vely.”

And later?We are talking about the future,about the next step. The resear-chers have looked at biodiver-sity in young and middle-agedforests (30-70 years). In thesemiddle-aged forests, a numberof red-listed lichens were found,

a species group that is thoughtto be sensitive to forestry. Butthey did not grow so much onthe new forest generation treesand were mostly found on theolder residual trees and old logs,i.e. structures that had been leftin the forest. This was shown,for example, in a survey carriedout by SLU in Hälsingland.“Most of the species don’t

seem to disperse to the youngtrees, but it’s still encouragingto find species particularly onolder deciduous trees and deadwood – these are the types ofstructures that are retainedtoday,” says Lena Gustafsson.But, I say, now it’s time

to harvest the forest again.Rotations are short andyou say that the spe-cies don’t even havetime to move to thenew trees before fel-ling. Do the speciessurvive intothenext

Retention of trees as a conservation practice increases variety in forests, thereby improving the chances ofpreserving biodiversity. And in the future, when the retention sites have matured and grown into a forestlandscape where conservation measures are still applied, the measures have even greater effect. Lena Gus-tafsson, Professor in Conservation Biology at SLU, is hopeful about the future.

Text | sverker johansson, [email protected] | Photo slu

retention IMPORTANT FOR BIODIVERSITY

THEME | smart tree retention


there are often fine logs on theground, and it’s important notto drive over them and destroythem. We should also workmore with restoration of themiddle-aged forests. There isgreat potential, using directedmeasures, to increase the pro-portion of deciduous trees andthe amount of dead wood inthese forests.”

Loss of species in the long term?This type of young forest hasalso been studied in Uppland.Red-listed lichens were onlyfound in five percent of thestands and the quantitieswere also much lowercompared with Häls-ingland.“This may be be-

cause many of theNorrland forestshave been clear-cutfor the first time. InUppland, the foresthas been used more in-tensively and over alonger period. Earlierusers have perhaps remo-ved more of the ‘lifebo-ats’,” suggests LenaGustafsson.

The dilemma?So there is a lot to thinkabout. Will the species conti-

nue to cling on to thesame old re-


ShortCutsShortCuts

Nature conservation is like the moose issue– more information is not crucial. It’s moreabout people’s attitudes.”

’’

rotation? Or is there a risk thatthinned forests will turn into astreet race that ends at the pre-cipice of final felling?According to Lena Gustafs-

son, this puts pressure on reten-tion actions also in themiddle-aged forests.“The old retained deciduous

trees look a bit scruffy in theeyes of the uninitiated. It isoften unattractive trees that areremoved in thinning. Also,

THIS IS SMART TREE RETENTIONThe research programme aims togive answers to how retentionapproaches can be designed to ef-ficiently promote biodiversity,while also examining the aesthe-tics, i.e. how attractive the reten-tion is to people in the forest.Researchers also analyse how theactions of various stakeholders af-fect the practice of retention. Furt-hermore, the researchers aim toshow what future forests, contai-ning the effects of the retentionmeasures, will be like.

In more concrete terms, issuesstudied in around ten projects inc-lude: how retention practices canbe adapted to regional conditions,how retained structures are to bemanaged, and if retained trees fa-cilitate re-establishment of species.The research programme also stu-dies cost-effectiveness and looksat the situation internationally andmakes comparisons. From a socialscience perspective, the resear-chers consider the attitudes of sta-keholders, and how thecommunication of the goals of re-tention works in practice. The pro-gramme has a multidisciplinaryapproach that involves social sci-entists, ecologists and remote sen-sing analysts.

The research programme iscoordinated by SLU, and is a colla-boration with Skogforsk and UmeåUniversity. The programme is fun-ded by the Research Council For-mas, which has provided SEK 20million over four years. A panel ofpractitioners, with representativesfrom bodies such as SCA Skog, theSwedish Forestry Agency, Sveas-kog, Södra Skogsägarna (forestowners’ association) and WWF arelinked to the project. Internationalexperts are regularly invited tomeetings.

READ MORE:www.slu.se,search for Smart Tree Retention

LENA GUSTAFSSON is Professor in Conser-vation Biology at SLU Department of Eco-logy, and is head of the Division ofConservation Biology. She works on biologi-cal diversity in the forest, and the effects andcost-effectiveness of nature conservation.

sidual trees – and how long willthey manage to do so?“Soon we’ll know more,” says

Lena Gustafsson. “We tend tolearn when we are faced withthe practical problems. It’s now,when the stands that containthe first retention structures areto be thinned, that the questionarises. But we now have moreknowledge behind us. In theprogramme SMART TREERETENTION, which is nowentering its final phase, we’reworking with knowledge synt-heses that will be useful in theseissues.”“If we regularly create gaps,

high stumps and other deadwood, encourage deciduoustrees, leave some dense forestunthinned, and reduce the pro-portion of pre-commercial thin-ning in this type of ‘poor’ forest,then I think this will help toprovide shelter and food formany species.”

Like the issue of the mooseLena Gustafsson points out thatnature conservation is ratherlike the moose issue, where thebalance between hunting andforestry has been discussed pas-sionately for over 150 years.“More information is always

good, but not crucial,” she says.“It’s more about people’s willsand attitudes. Do we want tohelp all species in the forestlandscape survive? Yes, we cando that. We already knowenough today to manage thistogether.”


6 ShortCuts | 2 | 2013 RESEARCH FOR TOMORROW’S FORESTRY

ShortCuts

“The holes abandoned by beet-les in high stumps and deadtrees form important nestingsites for bees, digger wasps, andwasps in young forest. Somespecies may be completely de-pendent on these types of reten-tion trees,” says Per Westerfelt,who is carrying out a doctoralproject at Skogforsk.The insects that Per Wester-

felt is studying are solitary, sa-proxylic stinging wasps like thelemon bee (Hylaeus) and fielddigger wasps (such as Passalo-ecus). They use old beetle holesto lay eggs and to develop lar-vae. However, although theseHymeroptera species, not leastpollinating bees, are importantfor various ecosystem functions,there is currently very little

knowledge about how they areaffected by tree retention.According to Per Westerfelt,

there is possibly a misconcep-tion that trees do not need to beleft in order to preserve orga-nisms that thrive in open forestlandscapes, such as bees andwasps.“When we leave dead wood

and high stumps, we’re creatingstructures in young forest thatare important or absolutely vitalfor the survival of the approx-imately 180 species of bees, dig-ger wasps and wasps that useholes in wood,” says Per Wester-felt. “Previously, fires andstorms created such wood, but

in modern forestry we mustcreate these types of sitesthrough retention measures.”

Reject felling stumpsIn one of the studies, Per Wes-terfelt is investigating the degreeto which holes in high stumps,dead trees and logs are used bythe stinging wasps comparedwith the holes in felling stumps.The results are clear.“Many stinging wasps comp-

letely ignored the fellingstumps, and only chose holes inhigh stumps and dead trees,”says Per Westerfelt.Why were the holes in ordi-

nary stumps not suitable?

THEY REJECT FELLING STUMPS

PreDators, PoLLinaters& Parasites Not just beetles, but also various Hymeropteraspecies, including the important pollinators, thriveon high stumps and dead trees. They move in whenthe beetles move out.

Text | kristina sundbaum | Photo sven tegelmo, Skogforsk

Insects on this page: Above,leaf-cutter bee (Megachile lap-ponica) and, below, the stingerwasp (Trypoxylon).

Preferhigh

stumps

THEME | smart tree retention



ShortCuts

“I can imagine that they pre-fer the higher holes because theconditions are more favourable,for example in terms of humi-dity and temperature. A nesthigh up is also better protectedagainst ground-living animalsthat may eat the larvae or de-stroy the nests. Furthermore,the felling stumps are oftenovergrown with mosses, lichenand brushwood.”

Retention is importantThe high stumps left as a con-servation measure seem to bevital for certain stinging waspsthat are looking for holes inwhich to build nests in youngforests. In forthcoming studies,Per Westerfelt will be examiningwhich type of dead tree is pre-

ferred by the stinging wasps –spruce, birch, aspen or oak –and will analyse the importanceof edge zones in creating a fa-vourable habitat.“It’s important to get confir-

mation that retention reallydoes provide benefit. We have aresponsibility to preserve diver-sity, and leaving retention treesand clumps in final fellingseems to be very important,”says Per Westerfelt.The project Bees and wasps

in young forests: managementimplications is part of the rese-arch programme, Smart Reten-tion.“Many stinging wasps comp-

letely ignored the fellingstumps, and only chose holes inhigh stumps and dead trees.”

Many stinging wasps completely ignoredthe felling stumps, and only chose holes inhigh stumps and dead trees

Per Westerfelt, in the middle of a doctoral project at Skogforsk.

’’


ShortCuts

RESEARCH PROGRAMMESWooD UtiLization Lars [email protected]. Phone: +46 18 188555Forest teCHnoLoGy Magnus [email protected]: +46 18 188596LoGistiCs Gert Andersson, [email protected] Phone: +46 18 188567

Forest BioenerGy Rolf Bjö[email protected]: +46 18 188509tree BreeDinG nortHBengt Andersson [email protected]: +46 90 2033358tree BreeDinG soUtH Bo [email protected]: +46 418 471305

siLviCULtUreLars-Göran Sundblad [email protected]: +46 90 2033369environment Jan-Olov Weslien [email protected]: +46 18 188505

UPPsaLa (Head office) Uppsala science Park,SE-751 83 Uppsala, Sweden Phone: +46 18 188500

eKeBo Ekebo 2250, SE-268 90 Svalöv, SwedenPhone: +46 418 471300

UmeÅ P.O. Box 3, SE-918 21 Sävar, Sweden.Phone: +46 90 2033350

www.skogforsk.seeditor in chief: Jan Fryk | Form: Pagarango | editor: Sverker Johansson, Bitzer | issn: 2000-2726Photos: Sverker Johansson unless otherwise stated | translated by: Leslie Walke, CommunicAID | Printed by: Gävle Offset, 2013

Retained aspen trees serve as ‘life-boats’ for the lichen species of theold forest. They do not disappearwhen the trees around the aspenare felled, despite their habitatchanging dramatically. Further-more, the aspens quickly attractmore lichen species when they areretained on the clear-cut.

“The aspen is a pioneer tree, soit’s perhaps not so strange that it isa suitable habitat for light-tolerantlichens,” says Johanna Lundström,who carried out the study. Howe-ver, we had thought that more li-

chens from the old forest would di-sappear.”

Johanna Lundström has studiedthe aspens that wereleft as retention treesafter felling in Jämt-land and Medelpad.In the shorter pers-pective (0-4 yearsafter felling), she andher colleagues founda total of approxima-tely 130 lichens onthese retentiontrees.

Lichen flora favouredIn the longer perspective, the li-chens appear to benefit from theretention. After 10-16 years, whenthe retained aspen is surroundedby young forest, the total numberof lichen species is approximately180. Many species from the old fo-rest remain, and new, more light-demanding species have arrived.

From the tree crowns?But how can the aspen so quicklyattract so many more lichen spe-cies? The researchers do not knowfor sure, but they have theories:

“When the aspens are isolated,the environment on the stems be-

comes more heterogeneous. Thedifference between the north andsouth side becomes bigger, and

many of the treesstart to lean,” expla-ins Johanna Lund-ström. ”Morevariation on thestems enables morespecies to find sui-table habitats.”

”The new speciesmay have spreadfrom other trees in

the adjacent forest, or they mayhave spread downwards from thecrown of the aspen. We don’tknow so much about the speciesthat live higher up on aspens stan-ding in closed forest in this area,”continues Johanna Lundström.“Many lichens are also dispersedby wind, and a free standing aspenmay be easier to colonize."

What other advice can you give?“Aspens are needed in forests ofdifferent ages in order to benefitthe entire lichen flora,” says Jo-hanna Lundström. “Consequently,aspens must be allowed to regene-rate on the site. Leave a vegetation-free buffer zone around the aspenson the clear-cuts.”

ASPENText | sverker johansson, [email protected] | Photo | fredrik johansson & ulrika nordin

A LIFEBOAT FOR LICHEN

“What have we here?”Field worker Fredrik Jonsson checksout the lichen species.

Johanna Lundström researching intothe lichens of the aspen.

PHO

TO: S

VER

KER

JOH

AN

SSO

N/B

ITZE

R


creo

shortcuts - skogforsk · 2019. 1. 14. · 4 shortcuts | 2 | 2013 shortcuts “the old trees and the...

Documents