How to make herbarium Alexey Shipunov December18,2019 Shipunov,Alexey.Howtomakeherbarium: ashortmanual. December18,2019version(draft).20pp. Onthecover: Dactylorhizamaculataherbarium,scannedimage. Thisworkisdedicatedtothepublicdomain Tothememoryofmymentor, VadimTikhomirov Contents 1 Herbariumcollectionanddesign 5 1.1 Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Howtocollectplants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.3 Whenyoureturnfromatrip . . . . . . . . . . . . . . . . . . . . . . . . 9 1.4 Drying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1.5 Labeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.6 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.7 Storageandhandling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2 Specialcases 17 2.1 Mossesandlichens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.2 Algae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Latinname . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Recommendedliterature 19 4 1 Herbarium collection and design Botanical traditions vary between countries and botanical schools. Here I will de- scribethewayplantcollectionistypicallydoneincountrieswithGermanbotanical tradition, e.g., in Russia and Ukraine. I believe that this way has some advantages overthetypicalAmericanway,anddeservesafurtherexpansion. 1.1 Preparation Plantcollectionisseriouswork,andoneshouldalwayshaveaclearunderstanding ofyourplans. Thereareatleasttwotoolstokeepwithyouonacollectiontrip:aherbariumtrowel (shovel)andafieldpress.Thetrowelisneededtotakeplantsoutofthesoilwithun- dergroundpartsrelativelynon-damaged. Iftheplantistoolong(likegrapevine)or thisisatreeorbigshrub,undergroundorgansareignored,andtrowelisnotneeded. However,youalwaysneedthetrowelifyoucollectherbaceousplantsorevensmall shrubsorshrublets. Itispossibletouseanythingasatrowel(youcanevendigthe plantoutwithyourhands); thebestchoiceisathickknifewithawide(about3cm orwider)blade,flatchiselorspeciallysharpenedfragmentofasteelpipe(Fig.1.1.)1 Atypicalgardenorkid’strowelswillnotworkwell.Youcanalsouseapenknifebut notforlongsinceitsbladewillsoonbreakand/orgoblunt. Second,you need the field press to straighten and press the plant right on the col- lectionspot;thiswillpreserveitingoodconditionforthenextstageoftheprocess. Ifthecollectiontripisshortandplantsrough(e.g.,donotwitherfast),itispossible togatherplantsintoaplasticbag. However,inthislastcase,itispossibletoforget whereexactlyeachplantwascollected. Thefieldpressisessentiallytwopiecesofplywoodorcardboardwiththesizeslightly exceedingthetypicalcollectionherbariumsheet(44×30cm).Youcanmakethem, forinstance,34×47.5cm.Thereshouldbefourholesontheperimeter(forexample, 1AllpicturesmadebyMichailBoldumanu.ManythankstoKylePayforgrammaticalcorrections. 5 Figure1.1: Differentherbariumtrowels. 2.5cmindiameterlocatedon4.5cmdistancesfromcorners);theseholeswillhold two straps (pieces of rope): see Fig. 1.2. In order to make the field press easier to handle, there should be the third strap between two upper holes of the one (top) side.Placenewspapercollectionsheetsinside.Youtypicallyneed20–30perpress— thenumberdependsonhowmanyplantsyouwanttocollect.Everycollectionsheet shouldcontainoneplant.Tietwomainstrapsinbows,andfieldpressisready. Figure1.2: Fieldpress. Apart from field press and trowel, the bare minimum of collection equipment in- cludes pencil (not a pen!) and paper (preferably sticky) for labels,plus all possible fieldtripequipmentyoumightfindnecessary,fromthecartocameraandraincoat. 6 1.2 How to collect plants Nowtothecollectionprocess. Choosethehealthy,averageplantwithbothvegeta- tiveandreproductiveorgansavailable.Ifplantsaretoobig,choosethesmallestbut notanuglyone. Theselectedplant(ifitisnotavine,likemorning-glory,orbigwoodyplant)should betakenoutwithroots.Thisisespeciallyimportantifyoucollectgrassesorsedges whereoneofthemostsignificantdeterminationcharactersisthewayofvegetative reproduction (intravaginal or extravaginal), which is visible only on underground parts. Species of dock differ by the presence of taproot, and there are many more specieswhereidentificationrequiresundergroundparts. Ifyoucollectareallyrare plant,youmayleaveundergroundpartsinthesoiltogiveitthechancetoreproduce. Immediately after digging out the plant,you need to untie the field press,take the topmost (one of field press sides, side with handling strap must always be upper!) collectionsheet,openitandplacetheplantonitshalf. The next step is to straighten the plant (this is not a final straightening but still veryimportantone).Thegoalistoconvert3Dreal-worldplantsinto2Dherbarium samples.Youwillneedtomakealltheimportantpartsasmuchexposedaspossible. Donotcrumple! Bendingisprohibitedwithoutnecessity. Youshouldpressmostoftheplantsurfacetothepaper,makingitflat.Toholdparts flat,you can use various hard and heavy things like stones,coins,trowel,etc.,and finally, your own fingers. If there is a place where leaves and/or other organs (like flowers)willoverlap(pleasetrytoavoidoverlapping),youshouldputtherethesmall piece of paper. Otherwise, these contact places will turn black during the drying process.Some(2–3)leavesgoodtoplacereversely,thebacksideup. By the way,these small fragments of paper are extremely useful and never do any- thingbad. Themoreofthemyouinsert,thebetteristhequalityofthesample. Do notforgettoremovethemwhentheplantisdry. Flowers should be thoroughly straightened to show all its primary organs—calyx, corolla, stamens, and pistil. If petals are fused, do not straighten them. Be very carefulwiththedelicateflowersofsomeplants(likeflaxoreveningprimrose). Itis betternottotouchthemwithhandsbutusepreparationneedleinstead.Todrythese flowersthoroughly,Irecommendtoplacethembetweentwosheetsofthinpaper(or withinonebentpaperpiece)andputthepieceofcottonwoolabove.Youcandothe samewithothercomplicatedparts.Donottouchthisflowerpaperuntiltheplantis completelydry! Afterstraightening,slowlyclosethecollectionsheetfromlefttoright(donotforget to remove everything which was used for holding). While holding the whole pile, 7 take empty collection sheet from bottom of the pile and place it above the sheet, whichwasjustused. Sofar,Iexplainedhowtodealwithplantswhosesizeiscomparablewiththecollec- tionsheet.Nowforthemorecomplicatedcases. What if the plant is bigger than the collection sheet? Many grasses and grass-like plants are. In these cases, you should bend the plant, first pressing your nail to plant leaves and stems on the 1–2 cm distance from the top edge of the paper. If many parts are coming out, bend them exactly on the same level. Sometimes, it ismorehandy(butnutquiteaesthetic)tobendalowerpartinsteadofupperparts. Rarely, it is possible to cut out outstanding parts—but please do not damage the plantandalwaysleavetracesofwhatwasdone(toletothersknowthatsomeorgans werelocatedhere). Long plants like vines, shrubs, and trees are collected in parts, typically branches with leaves and reproductive organs. Note that since it is impossible to esti- matethesizeofsuchaplantfromwhatwascollected,thecollectormustnote theheight(orlengthforvines)onthelabel. Bigherbaceous plants or plant parts. If the plant does not fit after bending from above,bend in from below. If it still does not fit,continue bending up to 5–6 times(especiallyifplantsarenarrow,likerushesandsedges). Otherwise,you mightapplymoredamagingprocedures—cuttheplantinafewparts,discard what is not too valuable (typically, the middle) and keep others. Sometimes, you need to place a disintegrated plant on several collection sheets (do not forgettomentionitonlabels).Thisishowtheycollectpalms. Ferns arecollectedasawhole,butiftheplantistoobig,itwillbeenoughtokeepthe halfoftherhizome(cutitlengthwise)and1–2wholeleaves(fronds),preferable withsporangia. Spikemosses and other creeping plants might also be collected in parts. It is enoughtokeeponesegmentwithroots,leaves,andspikesorflowers. Waterplants arebettertoexpandinwater,onasheetofdensewhitepaper(likethe paperusedformounting,seebelow)withpreparationneedle.Thisisthetypi- calwaytocollectduckweedsandotherplantsfloatinginwater.Thethickpaper sheetwiththeself-adherentplantisthenplacedinsideofcollectionsheet. Plantparasites should be collected with a host. Sometimes, non-green parasites will change color significantly after drying so it is better to note the color on thelabel.Thesameisrecommendedforplantschangingcolorsoftheirflowers (likeflaxes). 8 Juicyplants, cacti,plantswiththickrootsandstemsneedspecialtreatment.Some- times, it is enough to cut out lengthwise (with sharp knife) part of the leaf, stem,orroot.Sometimes,itisbettertoleaveonlyskin.Inextremecases,you willneedtoboilthejuicypartinwateroreveninethanol(however,remember thatthelastprocedurewillreducethepossibilityofDNAextractionfromthe sample). Smallplants, wheneveryplantissignificantlysmallerthanthecollectionsheet,it isbettertocollectinlargerquantities,tofillthesheetwithplants. Donotdo itforrareplants,though. Inall,themostimportantonthisstepistokeepallsignificantmorphologicalchar- actersinplace. Donotforgettowritethedraftlabelandattachittothesheet! Tosavetimeinthefield,youmaywanttokeepakindofdatabasewherealllocations arenumbered.Thenplantlabel(stickypaperispreferable)willhaveonlynumbers, like “245-18 img 2309”. First (245) is the number of location; second (18) is the number of collected plant; and the third (img 2309) is the name of the intra-vital photographofthecollectedplant.Ihighlyrecommendphotographingeachsample, andthebestistodoitseveraltimes.Andifyourcameraalsohasanabilitytoinsert GPScoordinates(geo-reference),thesephotosaresimplyindispensable. When you finish collection on a particular spot,tie the field press tightly (you may want to press it with knee or even foot,but be sure that plants do not damage one another).Asyousee,pressingstartsatthetimeofcollection. 1.3 When you return from a trip The first thing is to prepare the drying tools and start the main straightening; the sooner,thebetter—otherwise,plantswillwithercompletelyandwillbeunavailable for further processing. This is especially important if the weather is hot. However, in a cool and humid place,the field press could lay for 5–10 hours,this is why the rainisnotaproblem(youcanevendropthefieldpressintowaterwithoutanyreal damage.) The main drying tool is a drying, permanent press (or simply “press”, do not mix it with field press!) Typically,this is two wooden frames made from 4 planks each, withseveralcross-bars,sometimesalsowithsteelwiremeshononeside(Fig.1.3). Tostartdrying,youneedtoputallreadycollectionsheetsintothepress,interleaving themwithdryingsheets.Ifyouhavethenon-printednewspaper,itisagoodideato useitforplantsheets,andusecommon(printed)newspaperforinterleaving(drying) 9 sheets.Inthatway,thedangeroflosingyourplantbyaccidentwhenchangingdrying sheetsisreduced. Figure1.3: Dryingpress(“press”). Pleasenotethatitwillbeimpossibletostraightentheplantthethirdtime(youcan onlycorrectsomeparts).Ifinthefieldyoudonotactuallyneedtoexpandandflatten welltheroughparts(theywillbesofterwhenplantwitherabit),nowthisshouldbe done with all possible accuracy. Compound leaves of legumes and similar plants require even more work. Check plants again for crumples and unnecessary bends. Do not touch delicateparts (like flowers),but ifflowers were rough,carefully place them in paper and possibly add cotton above. Fill the whole paper surface with a plant,exceptonecorner(typically,bottomleft—forlabel). Iftherearetoomanypartstostraighten,youmightapplysurgeryandcutoutsome— but please always leave “stumps” which show that there was a part which is now removed. Whenfinished,closethecollectionsheetandputitintothepress. Theorderisfol- lowing: ifthepresshasnowiremesh,placecardboardonitsinnerside(ifthereisa wiremesh,nocardboardrequired),then2–6dryingsheets(emptynewspapers),then the first collection sheet with the plant processed,then 1–2 drying sheets (more if your plant is wet and/or thick),then next collection sheet with a plant,then again dryingsheets,andsoon. The total number of plants in the press varies and depends on the plant type. As a rule,itisnotrecommendedtohavemorethan50plantsperpress.Themoreplants areinside,theslowerandmorebadlytheydry.Whenthepileisready,put2–6drying sheets above,then (if there is no wire mesh) cardboard and finally,the second half 10