Blaga: The plumigera outbreak evolution in the Siret Basin (Romania) between 2002 and 2005

THE OUTBREAK EVOLUTION IN THE SIRET BASIN (ROMANIA) BETWEEN 2002 AND 2005

Tatiana Blaga Forest Research and Management Institute - Forest Station Bacău - ROMANIA E-mail: [email protected]

Abstract

This poster presents the research results obtained between 2002-2005 in some broadleaf stands (mostly oak-based stands) from the east region of the country, stands with Acer species in composition, infested with Ptilophora plumigera (Lep. ). In the Siret basin the average larvae density was of low (forest local districts: Brodoc, Vaslui-Vaslui, Focşani,Panciu - Focşani, Podu-Iloaiei - Iaşi, Truşeşti, Darabani - Botoşani) to very high level (forest local districts: Căiuti-Bacău, Adjud, Griviţa - Vrancea ). The insectivore birds (Ficedula albicollis, Turdus philomelos, Emberiza citrinella) and some Carabidae species (Abax ater, Carabus coriaceus, C.silvestris, C. convexus and Molops piceus) have an unnoticed importance in Ptilophora plumigera outbreak limitation.

Keywords: Ptilophora plumigera, outbreak, Siret basin

1. Introduction

Starting with spring of the year 2001, in some stands from the east region of the country, where Acer species are in composition, defoliations of different intensities were recorded, produced by larvae of Ptilophora plumigera Denis et Schiffermuller (, Notodontidae). In spring 2001, the outbreak of this spread also in other stands from the Siret basin (Buzau, Bacau, Vaslui, Vrancea, Iasi, Neamt, Botosani counties).

2. Materials and research methods

The researches were carried out in laboratory as well as under field conditions. The observations were carried out in oak-based stands with Acer species in composition and the infestation level with larvae of Ptilophora plumigera was established. The qualitative elements of the outbreak were established using pupae analysis. In order to point out the impact of some insectivore birds upon the P. plumigera larvae, there were carried out stomach content analysis using material collected from birds coming from the infested stands.

3. Results and discussion

3.1 The infestation level in the phase of larvae

In the last four years, the defoliator was present all along the Siret basin (table 1) and it spread in the majority of the stands, in some areas producing high and very high defoliation levels.

IUFRO Working Party 7.03.10 Proceedings of the Workshop 2006, Gmunden/Austria 229 Blaga: The Ptilophora plumigera outbreak evolution in the Siret Basin (Romania) between 2002 and 2005

The average density of the Ptilophora plumigera larvae was mostly low (forest local districts Brodoc and Vaslui - Forest Regional District Vaslui; Focsani, Panciu-Vrancea; Podu-Iloaiei - Iasi; Trusesti, Darabani - Botosani), medium (forest local districts Gugesti, Dumitresti - Forest Regional District Vrancea) (table 2), but is recorded also very high values characteristically for powerful and very powerful infestations (forest local districts Caiuti- Bacau, Adjud-Vrancea and Grivita-Galati).

Table 1: The conditions of the stations and the stand in the forests infested with Ptilophora plumigera located in the basin of the Siret river

Forest Unit Site Forest site Forest Compartment Composition Age Forest Altitude Exposition Direction Manag. class type District type 1 2 3 4 5 6 7 8 9 10 11 12 A 9 Mo 1 Pa 32 3 5153 5321 170 E 13 A 3Pi 3Mo 3Pa 1 Dt 22 2 5153 5321 290 NV Căiuti VII 14 A 6Pi 2Mo 1Pa 1Dt 22 3 5242 4331 253 V 14 B 7Mo 2Pa 1Go 22 3 5242 4331 200 NV Bacău 14 C 5Pi 3Pa 2Mo 22 3 5132 5131 310-380 NV 23 A 4 St 4Pa 1Fr 1Ju 36 2 5153 5312 220 E Traian IV 24 A 8St 1 Go 1Ju 61 2 5153 5312 220 Plane 25 A 5St 1Go 2Ca 2Ju 136 3 5254 9911 luncă E Zeletin I 6 5 Go 3Ca 1Fr 1Ju 55 3 6152 5323 260 E 32 5Go 1Ci 1Ju 1Fr 2Dt 80 2 7430 5321 200-220 E 33 5Go 1Ci 1Ju 1Fr 2Dt 50 2 7430 5321 210 SE Trusesti II 35 4St 2Go 2 Ju 2Dt 70 3 7420 5513 210 V Botosani 44 7Go 2Fr 1 Ju 60 3 7420 5113 110-120 NE 46 7Go 1Fr 1Ci 1 Pa 60 3 7420 5323 120-210 NE Darabani II 15 B 3Ul 2Ju 1Ci 2Te 2Dt 53 3 7430 6213 120-160 NE 13 A 3St 3Go 1Fa 1Str 1Ca 1 Ju 35 2 5153 5312 300 SE 18 4Go 1Fa 1St 3Ca 1 Ju 55 2 5153 5312 290 SE Pascani I 26 D 6Go 3Pa 1Dt 20 2 5153 5312 300 E Iasi 27 A 6Fa 2Go 1Ca 1 Pa 120 2 5153 5312 300 SE 28 4Go 3St 1Fa 1Ci 1 Ju 45 2 5153 5312 300 Plane Podu Iloaiei V 5E 5Fr 4Ju 1Dt 66 3 7540 6311 190 Plane 14 6Go 2Ul 2Ju 32 3 5153 5321 130 SE Adjud IV 17 6Go 2Ul 2Ju 33 3 5153 5321 160 SV Focsani 19 6Go 2Ul 2Ju 32 2 5153 5321 170 E Gugesti VI 104 4Ju 2Sc 2St 1Ul 1 Ju 37 3 7420 5113 200 Plane Panciu I 68 C 8Go 1Ju 1Dt 57 3 5132 5121 360 SV Roman II 43A 5St 4Pa 1Dt 21 3 7430 6211 320 Plane Piatra 12 4Go 4Ca 1Dt 1Ju 25 3 5152 5113 330 Plane Neamt Tg.Neamt V 61D 1Go 5Ca 1Dt 2St 1Pa 40 3 7430 6131 330 Plane 48 5Te 3Fr 1Go 1Ju 52 2 7430 5511 300 V Vaslui Vaslui VII 50 5Te 3Fr 1Go 1Ju 52 2 7430 5511 300 V 52 5Te 3Fr 1Go 1Ju 52 2 7430 5511 300 V

Table 2: The stomachal contents at the some species of the birds from the forests with infested with Ptilophora plumigera (2004 - 2005)

The amount of the spent food Defoliators Coleoptere Dipte- Hyme- The vege- Forest Unit Lepidoptere Forest Nr. re nopte- Chi- Gas- table (compo- Management Species of the birds Curcu- Chry- Sil- The scraps of district pcs. Geo- Tor- (Syr- re Cara- Scara- lopo- tro- (grass, boods, sition) Compartment Ptilo- Noctu- lioni- some- phi- metri- trici- phy- (Formi- bidae beidae dae liti beads, phora idae dae lidae dae dae dae dae) ca sp.) seeds)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Ficedula albicollis ≈ 150 pcs. 1 2pcs. - - - - 8pcs. ------(male) ∅=0,1-1,0mm Emberiza citrinella 14pcs grass Gugesti 1 - - - - - 2pcs. ------2pcs. VII (male) . 1x2,5 cm Vaslui 4Te3Fr1Go 48 ≈ 5000 pcs. 1Ju1Dt Sturnus vulgaris 2 - 5pcs. 22pcs. 4 pupa - - - 2pcs. 1pcs. 1pcs. 1pcs. - - grass ∅=0,1-1,0mm ≈ 300 pcs. Lanius collurio 1 ------≈ 3 pcs. - - - ∅=0,1-1,0mm 1 bood grass Lanius collurio (malel) 1 ------1pcs. 1pcs. - - - Carligi II 3 pieces Roman 5 St 4Pa 1 43 at 1,5 cm Dt Emberiza citrinella 0,01-0,5 mm 1 2pcs. 2pcs. 12pcs. - 2pcs. - - - 3 pcs. - - - - - (male) 1500 pcs.

IUFRO Working Party 7.03.10 Proceedings of the Workshop 2006, Gmunden/Austria 230 Blaga: The Ptilophora plumigera outbreak evolution in the Siret Basin (Romania) between 2002 and 2005

3.2 The importance of the soil fauna and insectivore birds

As a component of the soil fauna some predator species of Carabidae were identified with impact upon the Ptilophora plumigera populations in larvae phase, among which the following species were more abundant: Abax ater, Carabus coriaceus, C. silvestris and C. convexus, Molops piceus, Pterostichus melas (table 3). Also, as a result of the stomach content analysis, there were found out larvae of Ptilophora plumigera in the fourth and fifth instars, as well as in the stomach of several insectivore birds (Ficedula albicollis, Turdus philomelos) and in the stomach of a granivore one (Emberiza citronella).

4. Conclusions

The researches carried out between 2001 and 2005 regarding the defoliator Ptilophora plumigera pointed out several important aspects presented in the following lines: Ptilophora plumigera is a known defoliator just since 1940, but which did not cause important defoliations upon Acer species and, for this reason, it does not appear on the forestry prognosis pests' list. Between 2001 and 2003 the insect started the outbreak in the Siret basin, in oak-based stands with Acer species in composition. The larvae of Ptilophora plumigera appear and develop in the same time with the principal oak defoliators (Geometride, Tortrix viridana). Pupation takes place in the soil. The Carabidae species have a noted importance in the soil fauna (Abax ater, Molops piceus, Carabus coriaceus, C. silvestris and C. convexus etc), as well as the insectivore birds (Ficedula albicollis, Turdus philomelos) and granivore ones (Emberiza citronella) have an impact on the Ptilophora plumigera populations in larvae phase. Because of the low participation of the Acer species in the composition of the oak-based stands and the possibility of natural extinction of the outbreaks of Ptilophora plumigera (predators, parasites), it is not recommended to apply control measures, except for the high important areas where the Acer species have a significant participation percentage in the stand composition and using, preferable, bio-products.

Fig. 1: The map- The surface areas of the defoliator Ptilophora plumigera in the forests from Moldova-Romania, 2002-2005

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y = 9.1337 + 1.2660 * Density y = 15.170 + 0.09039 * Density Correlation: r = 0.45516 Correlation: r = 0.36542 26 32

22 28

24 18

20 14

16 10

The defoliation %

The defoliation % 12

6 8

4 2 -1010305 07090110 0123456789

The density of the eggs % The density of the eggs %

Fig.. 2: The correlation between the defoliation and the density Fig. 3 The correlation between the defoliation and the density of of Ptilophora plumigera eggs was recording in Moldova the Ptilophora plumigera eggs was recording in Moldova (Romania) in the 2004 year (Romania) in the 2005 year

y = 2.5305 + 1.1719 * Density Correlation: r = 0.62520 6 16 The density of the eggs - % 14 5 The density of the caterpillars - % 12 4

10 3 8 2 6

4 1

The defoliation - [%] 2 0

0 Cornatel - Chiosu - Gugesti - Cirligi -

-2 Caiuti Adjud Vaslui Roman -113579

The density of the caterpilar - [%]

Fig. 4: The correlation between the density of Ptilophora Fig. 5: The correlation between the density of caterpillars and the plumigera caterpillar and the defoliation from Moldova density of eggs of Ptilophora plumigera was recording in Moldova (Romania) (Romania)

100

80 40 60 30 %

40 % 20 20 10 0 0 l i i i i a i e n t u g t it t ia s s li s iosu n a a e io r e rnatel h rn r b h a g o C o T lu C C u Vindere Var Gugest u G C Guranda C B Forest the density of larvae -% Forest the density of larvae - % 2002 year the defoliation -% 2004 year the defoliation - %

Fig. 6: The correlation between the density of larvae and the defoliation Fig. 7: The correlation between the density of larvae and the was being recorded in Moldova (Romania) in the 2002 year defoliation was being recorded in Moldova (Romania) in the 2004 year

10 9 8 7 6 5 % 4 3 2 1 0 i l t u e s Carligi Chio Cornat Guges Forest the density of larvae - % 2005 year the defoliation - %

Fig. 8: The correlation between the density of larvae and the defoliation was being recorded in Moldova (Romania) in the 2005 year

IUFRO Working Party 7.03.10 Proceedings of the Workshop 2006, Gmunden/Austria 232 Blaga: The Ptilophora plumigera outbreak evolution in the Siret Basin (Romania) between 2002 and 2005

Table 3: The species of the identified birds in the period of nested in the stands infested with Ptilophora plumigera in Moldova – Romania

Egg Nr. The species of the birds Diet Nestle Adjud Vaslui masses 2 Observations crt. Adjud 1 ACCIPITER GENTILIS C CO + + 2 ACCIPITER NISUS C CO + - 3 AEGITHALOS CAUDATUS I CO - + 4 ANTHUS TRIVIALIS I S + + + 5 ASIO OTUS C,I CO + - 6 ATHENE NOCTUA C,I SC + + 7 BUTEO BUTEO C CO + + 8 CAPRIMULGUS EUROPEUS I G + + 9 CARDUELIS CANNABINA G SA - + 10 CARDUELIS CARDUELIS G CO + + + 11 CARDUELIS CHLORIS G CO - + 12 CERTHIA FAMILIARIS I SC + + 13 CICONIA NIGRA C CO - - 14 COCCOTHRAUSTES COCCOTHRAUSTES G CO + + 15 COLUMBA OENAS G SC + - 16 COLUMBA PALUMBUS G CO - + 17 CORVUS CORAX O CO - + 18 CORVUS CORNIX O CO + + 19 CORVUS MONEDULA O SC - + 20 CUCULUS CANORUS I CO + + 21 DENDROCOPOS MASOR I SC + + + 22 DENDROCOPOS MEDIUS I SC + + + 23 DRYOCOPUS MARTIUS I SC - - 24 EMBERIZA CITRINELA G S + + + 25 ERITHACUS RUBECULA I SA + + 26 FALCO TINNUNCULUS C CO + - 27 FALCO VESPERTINUS I CO + + + 28 FICEDULA ALBICOLLINS I SC + + 29 FICEDULA PARYA I SC - - + 30 FRINGILLA COELEBS G CO + + 31 GARRULUS GLANDARIUS O CO + + 32 HIPPOLAIS ICTERINA I CO - + 33 IYNX TORQUILLA I SC + - 34 LANIUS COLLURIO I SA + + 35 LANIUS MINOR I CO + - 36 LUSCINIA MEGARHYNCHOS I SA + + 37 MOTACILLA ALBA I SC + + + 38 MUSCICAPA STRIATA I SC + + 39 ORIOLUS ORIOLUS I CO + + + 40 PARUS CAERULEUS I SC + + + 41 PARUS MAJOR I SC + + + 42 PARUS PALUSTRIS I SC + + 43 PASSER DOMESTICUS G SC + + 44 PASSER MONTANUS G SC + + + 45 PHASIANUS COLCHICUS O S + - 46 PHOENICURUS PHOENICURUS I SC + + 47 PHYLLOSCOPUS COLLYBITA I S + + 48 PHYLLOSCOPUS SIBILATRIX I S + - + 49 PICA PICA O CO + + 50 PICUS CANUS I SC + + 51 PICUS VIRIDIS I SC + + 52 SITTA EUROPAEA I SC + + + 53 STREPTOPELIA DECAOCTO G CO + - 54 STREPTOPELIA TURTUR G CO + + + 55 STRIX ALUCO C SC + - 56 STURNUS VULGARIS I SC + + 57 SYLVIA ATRICAPILLA I SA + + 58 SYLVIA COMMUNIS I SA - + 59 SYLVIA CURRUCA I SA + + + 60 TROGLODYTES TROGLODYTES I SA + + 61 TURDUS MERULA I SA + + + 62 TURDUS PHILOMELOS I SA + + 63 TURDUS PILARIS I SA - - 64 TURDUS VISCIVORUS I CO - - 65 UPUPA EPOPS I SC + +

I 63,1 65,4 66,0 SC 36,9 40,4 38,0 DISTRIBUTION ON C 12,3 8,9 6,0 DISTRIBUTION ON CO 36,9 32,6 34,0 CATEGORY OF CATEGORY OF NESTLE DIET G 18,5 16,0 20,0 SA 16,9 15,4 20,0 O 9,2 11,0 10,0 S 9,3 11,6 8,0

Legend Diet Nestle C - carnivorous CO - crown of trees I - insectivorous SA - under stand G - granivorous S - soil O - omnivorous SC - hollow

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the density of the caterpillars - % 100 the defoliation - % 90 80 70 60 50 40 30 20 10 0 a ţ Traian Carligi Carligi Chiosu Chiosu Varnita Cioara Gugesti Gugesti Gugesti Gugesti Vinderei Cornatel Cornatel Cornatel Guranda Necori Bulubesti 2002 2003 2004 2005

Fig. 9: Density of caterpillars in comparison to the grade of defoliation

5. References

ENE M., 1971: Entomologie forestiera, Ed. Ceres, Bucuresti, p.371

ILINSCKII A. J.,1962: Opredeliteli vreditelei lesa, izdatelistva seliskohoziaistvennoi literaturi jurnalov i plakatov, Moskva,p. 162

CIORNEI C., RANG C., Blaga T., - 2005: Cercetari privind cunoasterea biologiei, ecologiei si elaborarea unor metode de depistare, prognoza si combatere integrata a defoliatorului Ptilophora plumigera din paduri de foioase cu acerinee in compozitie. Manuscris, ICAS Bucuresti

NEMES I., MARIN C. Voicu: Catalogul colecţiei de Lepidoptere Alexei Alexinschi, Muzeul jud. Suceava

PRICK M., SMEETS G.,1995: Ptilophora plumigera new for the dutch fauna (Lepidoptera: Notodontidae), Ent.Ber., Amsterdam, 55 (7), p.119-120

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