Prevalence, effect, and cause of apical meristem termination in the endemic Ocotea monteverdensis (Lauraceae) in Monteverde


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Prevalence, effect, and cause of apical meristem termination in the endemic Ocotea monteverdensis (Lauraceae) in Monteverde

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Prevalence, effect, and cause of apical meristem termination in the endemic Ocotea monteverdensis (Lauraceae) in Monteverde
Translated Title:
Frecuencia, efecto y causa de terminación del meristema apical en el árbol endémico Ocotea monteverdensis (Lauraceae) en Monteverde
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Bennett, Noah
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Lauraceae
EAP Spring 2018
EAP Primavera 2018
Costa Rica--Puntarenas--Monteverde Zone
Costa Rica--Puntarenas--Zona de Monteverde
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Ocotea monteverdensis is an endangered tree in the Lauraceae family endemic to the Monteverde, Costa Rica region. It consistently displays evidence of terminated apical meristems (TAMs). I explored the prevalence, effect and cause of TAMs in young O. monteverdensis trees. I measured height, DBH and herbivory as indicators of fitness and compared these factors between trees with TAMs and those without. After analyzing data from 220 trees across four different test sites, I found that TAMs were present at every test site across a wide range of heights. Between trees with TAMs and those without TAMs, I found that there was no statistical difference in DBH and in one case there was no statistical difference in height. One test site showed that trees with TAMs were significantly shorter than trees without TAMs. Thus, TAMs can have a negative effect on tree fitness. The reason for why only one site experienced a negative effect from TAMs is unknown. Possible theories include the variation in environmental factors and land-use history between the two sites. Regarding the cause of the TAMs, I did not find a definitive answer, though I did manage to largely rule out the hypotheses that vertebrates eat the apical meristem or that galls cause TAMs. In conclusion, I recommend that TAMs should continue to be studied by O. monteverdensis conservationists because they can negatively affect tree fitness. ( , )
Abstract:
Ocotea monteverdensis es un árbol en peligro de extinción de la familia Lauraceae, endémico de la región de Monteverde, Costa Rica. Los árboles en esta área muestran consistentemente evidencia de Meristemas Apicales Terminados (TAM en inglés). En este estudio, exploré la prevalencia, el efecto y la causa de los TAM en los árboles jóvenes de O. monteverdensis. Para esto, medí la altura, el DAP y la herbivoría como indicadores de la aptitud (fitness) y comparé estos factores entre los árboles con TAM y los que no presentaban TAM. Después de analizar los datos de 220 árboles en cuatro sitios diferentes, encontré que los TAM estaban presentes en todos los sitios y en un amplio rango de alturas de los árboles. Entre árboles con TAM y aquellos sin TAM, encontré que no había diferencia significativa en DAP y tampoco en altura. En uno de los sitios, los árboles con TAM eran significativamente más cortos que los árboles sin TAM, lo cual indica que los TAM pueden tener un efecto negativo en la aptitud del árbol. Se desconoce el motivo por el cual solo un sitio experimentó un efecto negativo de los TAM, pero podría deberse a variación en los factores ambientales entre los dos sitios y el historial de uso de la tierra por sus dueños. En cuanto a la causa de los TAM, no encontré una respuesta definitiva, aunque logré descartar en gran medida las hipótesis de que los vertebrados comen el meristema apical o que las agallas causen los TAM. En conclusión, recomiendo que los TAM sigan siendo estudiados por los conservacionistas de O. monteverdensis porque pueden afectar negativamente la aptitud del árbol.
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Student affiliation: Department of Environmental Science and Management, University of California, Davis
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Bennett 1 Prevalence, effect , and cause of apical meristem termination in the endemic Ocotea monteverdensis (Lauraceae) in Monteverde Noah Bennett Department of Environmental Science and Management University of California, Davis EAP Tropical Biology and Conservation Program, Spring 2018 8 June 2018 ABSTRACT O cotea monteverdensis is an endangered tree in the Lauracea e family endemic to the Monteverde , Costa Rica region. It consistently displays evidence of terminated apical meristems (TAMs). I explored the prevalence, effect and cause of TAMs in young O. monteverdensis trees. I m easured height, DBH and herbivory as indicators of fitness and compared these factors between tr ees with TAMs and those without . A fter analyzing data from 220 trees across four different test sites, I found that TAMs were present at every test site across a wide range of heights. B etween trees with TAMs and those without TAMs, I found that there was no sta tistical difference in DBH and in one case there was no statistical difference in height . One test site showed that trees with TAMs were significantly shorter than trees without TAMs. Thus, TAMs can have a negative effect on tree fitness. The reason for why only one site experienced a negative effect from TAMs is unknown. Possible theories include the variation in environmental factors and land use history between the two sites. Regarding the cause of the TAMs, I did not find a definitive a nswer, though I did manage to largely rule out the hypothes es that vertebrates eat the apical meristem or that galls cause TAMs. In conclusion, I recommend that TAMs sh ould continue to be studied by O . monteverdensis conservationists because they can negat ively affect tree fitness. Frecuencia , efecto y causa de terminacin del meristema apical en el rbol endmico Ocotea monteverdensis (Lauraceae) en Monteverde RESUMEN Ocotea monteverdensis es un rbol en peligro de extincin de la familia Lauraceae , endmico de la regin de Monteverde, Costa Rica. Los rboles en esta rea muestran consistentemente evidencia de Meristemas Apicales Terminados (TAM en ingls). En este estudio, explor la prevalencia, el efecto y la causa de los TAM en los rboles jven es de O. monteverdensis. Para esto, med la altura, el DAP y la herbivora como indicadores de la aptitud (fitness) y compar estos factores entre los rboles con TAM y los que no presentaban TAM. Despus de analizar los datos de 220 rboles en cuatro siti os diferentes, encontr que los TAM estaban presentes en todos los sitios y en un amplio rango de alturas de los rboles. Entre rboles con TAM y aquellos sin TAM, encontr que no haba diferencia significativa en DAP y tampoco en altura. En uno de los sit ios, los rboles con TAM eran significativamente ms cortos que los rboles sin TAM, lo cual indica que los TAM pueden tener un efecto negativo en la aptitud del rbol. Se desconoce el motivo por el cual solo un sitio experiment un efecto negativo de los TAM, pero podra deberse a variacin en los factores ambientales entre los dos sitios y el historial de uso de la tierra por sus dueos. En cuanto a la causa de los TAM, no encontr una

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Apical meristem termination in Ocotea monteverdensis Bennett 2 respuesta definitiva, aunque logr descartar en gran medida las hipte sis de que los vertebrados comen el meristema apical o que las agallas causen los TAM. En conclusin, recomiendo que los TAM sigan siendo estudiados por los conservacionistas de O. monteverdensis porque pueden afectar negativamente la aptitud del rbol. Conserving endangered species is of the utmost importance in biodiversity preservation. Maintaining biodiversity provides many benefits to society ranging from the ripple effects one species may have on an ecosystem to the potential for future medicinal use. Within an ecosystem, endangered species can perform essential functions such as feeding other species or providing population control. To rehabilitate these endangered species, the fitness of offspring should be explored and maximized. Ocotea monteverdensis is a critically endangered tree in the Lauraceae family endemic to the Monteverde area of Costa Rica. Its natural range spans between 1,200 and 1,450 m in alt itude and is restricted to the P acific S lope of the Tilar n mountains. Its estimated extent of occurrence of 172 km2, however only 43 km2 is suitable habitat ( Joslin et al. 2013). There are only an estimated 770 flowering trees left in this range ( Joslin et al. 2018). Little is known about this species due to its limited r ange and population, however efforts are being made to reestablish O. monteverdensis in its natural habitat ( Joslin et al. 2018 ). Organizations such as the Monteverde Institute and the Curi Cancha Reserve have planted cohorts of O. moteverdensis in various reserves across the tree’s range. Some private landowners have also elected to plant O. moteverdensis on their properties. The past decade has seen the planting of over 9,000 O. monteverdensis seeds (Joslin et. al, 2018) . Research focused on imp roving the fitness of these young trees can be invaluable to conservation efforts . One phenomena I and two of the world’s leading experts on O. monteverdensis, Dr. De v Joslin and Dr. Debra Hamilton, noticed was the existence of terminated apical meristems (TAMs) in young trees and saplings . In many plants there is evidence that a large segment of the apical meristem d ied and the plant was forced to sprout a new meristem which grew below the TAM . This process requires spending val uable resources that could be better used to increase the plants biomass and reach a reproductive life stage faster . Similar apical meristem termination has been observed in other plants . Much of the research surrounding TAMs identifies herbivores and gal l forming insects at the primary culprits (Throop and Fay, 2005; Throop and Fay, 1999; Whitham and Mopper, 1985). The main questions of this study are what is the prevalence, effect and cause of the apical meristem termination in young O. monteverdensis in Monteverde ? I predicted that saplings with TAMs would be shorter and have a smaller diameter at breast height ( DBH) than saplings without TAMs of the same age. Regarding the causation, I predicted that either a vertebrate consumed them, or insects kille d the apical meristem through herbivory or galls nearby created the TAM . I gather ed data from re forested sites where O. monteverdensis saplings were planted over the last decade.

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Apical meristem termination in Ocotea monteverdensis Bennett 3 MATERIALS AND METHODS My project took place over two weeks, with field data col lection occurring for eleven days in May 2018. Before doing any field research, I received data from Debra Hamilton on the location of saplings, the year planted and any information (height, TAM presence etc.) collected from the Rachel and Dwight Crandell Memorial Reserve and the La Calandria Reserve from the previous three years . Data was later gathered from Mauricio Ramirez on the state of trees in the Curi Cancha Reserve. I received data on roughly 500 individuals planted over the last decade. T he trees I studied were planted in 2008, 2009 and 2017, which makes them ten years old, nine years old and one year old respectively. Sapling location s spanned O. monteverdensis’ range. Data was also taken from 25 small (<2m in height) trees wher e the age was unknown. The plot planted in 2008 was in the Crandell Reserve and the plot planted in 2009 was in the Curi Canch a Reser ve. Data from 2017 saplings was taken at the La Calandria Reserve . The trees where age was unknown were found directly behind the Monteverde Institute. In Curi Cancha, the O. monteverdensis were planted in land that had recently been pasture . This plot had very few tall trees. Large grass sometimes reaching 1.5m in height covered the plot . Trees were planted in rows and spaced more t han three meters apart. In th e Crandell Reserve, trees were planted close together, sometimes less than one m eter apart. Trees in La Calandria were planted along a secondary forest trail. Trees measured behind the Monteverde Institute were found along the main road or within 25m of the main road. Two types of data were collected. One was measurement of sapling state and the other was an observation of saplings to determine the cause of TAMs . Sapling State Data w as recorded by hand in the field and transcribed to an excel sheet . Data gathered include d age of plant, plant identification number (PIN), height of central stem, diameter at breast height (DBH), number of leaves, presence of a TAM , distance between ground and the T AM (if applicable), distance between the TAM and the top of the new central stem or to the next TAM , presence of herbivory and number of leaves showing herbivory. Not all data types were collected for each plant. Saplings behind the Monteverde Institute were marked by a ribbontag for the duration of the study. Age of plant was gathered from Debra Hamilton’s data . Each plant was given a PIN if not alre ady provided by the Monteverde I nstitute or Curi Cancha data . PIN include d plot identification (A Z ) and tree number per plot (1100+). For example, the first tree in the first plot of Curi Cancha was labeled CC A1. Height of central stem was measured from the base of the tree, to the top of the tallest shoot using a ruler or clinometer . The measur ement was a straight line from the base of the tree to end of the central stem; curvature of the stem was not measured. Field assistant Sam Coursen helped with all measurements in Crandell and Curi Cancha for greater accuracy . We calculated clinometer data onsite and performed an observational check to ensure no miscalculations. We measured DBH using a DBH tape measure and counted number of leaves by ha nd with a counter . P resence of TAMs was defined in recently dead meristems as the discontinuation of one central stem and the growth of a new central stem longer than 1 cm. Older TAMs needed to have a dead woodystructure longer than 1 cm visible with no leaves attached. N ew stems differentiate d themselves from new branches by growing directly upwards instead of at a right angle. I measured the distance from the base of the tree to the point where the termination occurred and the distance from the top of the termination to the top of the new central stem or next termination point using a ruler or

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Apical meristem termination in Ocotea monteverdensis Bennett 4 clinometer . This measurement also took the form of a straight line and ignored curvature . Presence of herbivory was defined as an incomplete leaf. Cause of TAMs Observational data was recorded for each plant. Insects and galls on the plant were identified, counted and collected when identification was not possible in the field. Most insect identification was done with the help of Emilia Triana. Location of insect or gall in relation to the apical meristem and TAM was also noted. After creat ing f ive categories of TAMs based on physical appearance and properties (Appendix 1), I placed the found TAMs into one of these categories. Galls were split into three categories based on location and physical appearance (Appendix 2) . The 25 saplings of unknown age behind the Institute were observed at this level of detail. All other plants were observed if they contained interesting or inconsistent features. My observations ranged f rom 5 to 30 minutes over one or two days. Broad observations containing data on spacing of trees and climate were observed at each test site. RESULTS Over the course of the study, I measured or observed 220 sapl ings ; 25 from the Monteverde Institute, 45 from Crandell, 82 from Curi Cancha and 68 from La Calandria. Age of Monteverde Institute trees was unknown. Crandell trees were ten years old, Curi Cancha trees were nine years old and La Calandria trees were nine months old. Again, not all data was taken for every tree. Results are divided into three sections based on the three parts of my central question. Section 1: Prevalence TAMs were very prevalent , especially in older saplings . Every site I visited had trees with TAMs. More than 50% of the saplings in Crandell, Curi Cancha and behind the Monteverde Institute had TAMs, while less than 10% of saplings in La Calandria had TAMs. In total, 104 trees had TAMs and 106 trees did not. Out of the nine and ten year old Crandell and Curi Cancha trees, 85 had TAMs and 32 did not (Fig 1) . Of the 68 saplings from La Calandria, only 4 had TAMs, some of which occur red as low as 0.06m from the base of the plant. TAM s at the other three locations ranged from 0.2 m to 5.7m from the base of the plant . Section 2: Effect When analyzing tree fitness, I found no statistical difference in DBH between trees with and without TAMs at Crandell (T test (31) = 0.93, p = 2.04) or at Curi Cancha (T test (69) = 0.83, p = 1.99) ( Fig 2). There was also no statistical difference in height between trees with and without TAMs at Crandell (T test (34) = 0.82, p = 2.03), however there was a statistical difference in height between trees with and without TAMs at Curi Cancha (T test (39) = 2.02, p = 0.02) (Fig 3). Trees at Crandell were the tallest with an average height of 5m 2 .1m. Curi Cancha trees were the second tallest with an average height of 3.4m 2m. La Calandria had the shortest trees with an average height of 0.3m 0.1m ( F ig 4) . In addition to the trees being taller, Crandell also had a larger average DBH than Curi Cancha. The average DBH for Crandell was 6.3cm 2.4cm.

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Apical meristem termination in Ocotea monteverdensis Bennett 5 Th e average DBH for Curi Cancha was 5.5cm 4.6cm. Trees at La Calandria were too small to take DBH. Note that trees with a DBH of less than 0.8cm were not included ( F ig 5) . In La Calandria, saplings with no TAMs showed an average of 49% leaf herbivory while saplings with one TAM showed an average of 25% leaf herbivory. The s ample size was 44 saplings ; 42 saplings had zero TAMs and 2 saplings had one TAM ( F ig 6) . Section 3: Cause Through observation and collection, I identified 12 types of insects and 3 kinds of galls (See Appendix 2) that could potentially cause TAMs on the 25 saplings I sampled behind the Monteverde Institute . No insect or gall appeared on more than six saplings. I only found three insects or galls closer than 10 centimeters to the apical meristem (Table 1) . Collection of TAMs yielded 15 samples. Of those, 2 came from Crandell and 13 came from behind the Monteverde Institute . I found 8 complete TAMs, 2 partial TAM s, 4 stubby TAMs and 1 bumpy TAM. TAMs were collected on an “able to collect TAM” basis (Table 2) . See Appendix 1 for pictures. My observations also shed light on the development al stages of O. monteverdensis. The growth of O. monteverdensis occurs in patterns of branching and shooting. Trees tended to grow four or five branches and then produce a new stalk . The stalk was initially green and bumpy but slowly beca me brown and smooth. According to Dev Joslin, this is characteristic of most Ocotea found in Monteverde. Figure 1. Prevalence of TAMs across sampling locations.

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Apical meristem termination in Ocotea monteverdensis Bennett 6 Figure 2. Presence of TAM effect on DBH for Crandell and Curi Cancha. Figure 3. Presence of TAM effect on height for Crandell and Curi Cancha.

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Apical meristem termination in Ocotea monteverdensis Bennett 7 Figure 4 . Average height by l ocation. Figure 5 . Average DBH by l ocation. Figure 6. Average p ercent age h erbivory at La Calandria. Table 1. Insects and g alls found on O. monteverdensis. Name Total Trees Affected Total Individuals Found Proximity to Apical Mer i stem Branch Gall 6 9 >10cm Formicidae 5 25+ >10cm and <10cm Araneae 5 9 <10cm and >10cm Diptera 4 5 >10cm Mantodea 3 3 >10cm Leaf Gall 3 12 >10cm Orthoptera 3 4 >10cm Scale Bug 3 5 >10cm Coleoptera 2 1 >10cm and <10cm Adippe zebrina 2 8 <10cm Seedbug 1 1 >10cm Lacewing 1 1 >10cm Trunk Gall 1 1 >10cm Lepidoptera 1 1 >10cm Phasmatodea 1 1 >10cm 0 2 4 6 8 Crandell Curi Cancha La CalandriaTree Height (m) 0 2 4 6 8 10 Crandell Curi CanchaDBH (cm) 10 20 30 40 50 60 70 80 90 100 Zero OneAverage Percentage HerbivoryNumber of TAMs

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Apical meristem termination in Ocotea monteverdensis Bennett 8 Table 2. Types of TAM collected. See Appendix 1. Name Number Complete TAM (Burrowed) 2 Complete TAM (Not Burrowed) 6 Partial TAM 2 Stubby TAM 4 Bumpy TAM 1 DISCUSSION Section 1: Prevalence TAMs were extremely prevalent. They were present in every site . O ver half of the trees had TAMs in three out of the four sites . The only site where less than half of the trees had TAMs was La Calandria wh ose trees were less than one year old. Considering that I found TAMs at a variety of heights on older trees, it is likely that TAMs will develop on more trees as the La Calandria cohort grows taller. To better understand how TAM prevalence changes over tim e, I would suggest that a future study records the height and presence of TAMs on a yearly basis. It would be possible to do this through the Monteverde Institute’s annua l measurements of O. monteverdensis at La Calandria. Section 2: Effect Beginning the proj ect, I expected TAMs to have a negative effect on tree fitness in all categories tested because grow ing a new apical meriste m requires valuable resources. In comparing DBH and herbivory of younger trees , I found there was no disadvantage to TAMs. I n D BH and height of the trees in Crandell, there was no statistical difference at all. Perhaps this is because the sapling compensates for the lost meristem by growing higher and wider with its next shoot (Belsky et. al, 1993) . Results from Curi Cancha showed that trees with TAMs were significantly shorter than trees without TAMs. Similarly, p revious TAM research has shown that in some cases plant fitness is not affected by TAMs (Fay and Throop, 2005), while in other cases plants are negatively affected (Witha m and Mopper, 1985). Reasons for why the Curi Cancha trees saw a difference in height is unknown, however there are potential causes which could be tested. O. monteverdensis fitness can be greatly affected by external factors (Joslin et. al, 2013). Possible reasons for the difference in height between Crandell and Curi Cancha are the dif ferent climates, environments and history of the land. The field where O. monteverdensis were planted in Curi Cancha had been a pasture and the soil was compacted by years of cattle use. Soil compaction can severely reduce tree growth (Burger et. al, 2017). In addition to compaction, prior research in Central America has shown that lack of large vegetation in pastures can be difficult to recover from. E ven after fifteen years of reforestation, old pastures still lack an increase in soil elements vital to plant growth (Neumann Cosel et. al, 2011). Potential sources of error in this portion of the study come from our inability to count all TAMs that occurred throughout the life of the tree. Over time, dead branches fall off and tree

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Apical meristem termination in Ocotea monteverdensis Bennett 9 trunks grow thicker. In general, TAMs were lower on shorter trees and TAMs were higher on taller trees. Thus, i t is possible that a TAM which occurred to a tree at a young age was no longer visible. If this happened to a tree marked as “no TAM”, my results would be skewed. One solution for future studies would be to track the tree’s fitness from a young age and follow the development of TAMs. Section 3: Causation I had hypothesized that either a vertebrate was eating the apical meristem, insects were laying galls on the apical meristem or insects were killing the meristem through herbivory. I was unable to come up with a definitive answer, though I was able to rule out certain possibilities. It is also important to note that TAMs could be caused by multiple factors. Vertebrates were unlikely the sole cause of the TAMs because complete TAMs existed . Eight of the fifteen TAMs collected were complete, meaning that they were not visibly eaten by vertebrates. While six of the fifteen TAMs were missing a portion of the TAM , the reason for loss is unknown. It could have been a vertebrate eating the live apical meristem, or the TAM could have fallen off post mortem for another reason. It would also be physically hard for most herbivorous invertebrates to reach apical meristems across the TAM height range (0.06m to 5.7m) . Saplings less than one year old are more easily eaten by herbivores . It is also known that apical meristems of some new saplings are n ot fatally affected by herbivores. T he plant often regrow s around the dead shoot (Clark and Clark, 1985). Thus, macrovertebrate herbivory could be a cause of TAMs at younger ages. Evidence in opposition to herbivory playing a large role is the presence of anti herbivory secondary compounds in Ocotea such as phenylpropanoids (Da Silva et. al, 2017). Future observational research using camera traps could be conducted to look for macro vertebrate herbivory . Overall, there was no insect or gall which affected more than 25% of the saplings I observed. Of those, most insects were incapable of harming the plant. According to Emilia Triana, Formicidae, Araneae, Diptera, Mantodea, Orthoptera, scale bugs, seed bugs, lacewings, ad ult Lepidoptera and Phasmatodea are likely incapable of causing enough damage t o the apical meristem to create a TAM. They are primarily predators and leaf herbivores whose behavior does not affect the apical meristem. While some Coleoptera, such as weevils, can kill the meristem by b urrowing, not all TAMs were found to have burrowing holes (HoughGoldstein and LaCoss, 2012). It should also be noted that I was unable to f ind out who burrowed into the TAMs. Galls have the potential to kill young meristem s , however I never found a gall within 10cm of the apical meristem, nor did I find a gall near a TAM ( Dhileepan and McFadyan, 2001) . According to Emilia Triana, leaf galls are unlikely to have caused damage to an apical meristem. While some branch galls I found had no leaves beyond them , others had new growth. This would imply that at least some branch galls do not have a severe effect on the plant’s wellbeing. I only found one trunk gall, however there was another 14cm of growth above it with leaves (plant’s height was 65cm). Based on t he scarcity of the trunk gall occurrence and its limited effect on plant growth , it is un likely that trunk galls are a cause of TAMs; at least not a major cause. There was one “bumpy TAM” which looked like a gall, however after dissection, no cavities for larvae development were found (See Appendix 1).

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Apical meristem termination in Ocotea monteverdensis Bennett 10 While no conclusive evidence can be drawn from my observations regarding the cause of TAMs, the treehopper Adippe zebrina appeared a possible culprit. I only found them twice in the trees I thoroughly obser ved, however I saw them on two other O. monteverdenis saplings . In all cases, they were only found on new, green plant tissue. In two of the four cases, there were more than four individuals on the new, green apical meristem . In one of those cases, I observed egg sacks cut into the apical meristem . Debra Hamilton and Dev Joslin also noted that they observed many A. zebrina on young O. monteverdensis over the past ten years. Adippe are commonly found in Ocotea and have been known to lay their eggs in th e terminal buds of stems (Godoy et al. 2005). Some species in the treehopper family have been known to kill plants by feeding on the main stem (Sparks and Boethel, 1987). R esearch observing the fates of apical meristems with and without the presence of A. zebrina should be conducted to test this theory. Clearly, TAMs are prevalent in many O. monteverdensis and they can negatively a ffect the fitness of saplings . Thus , TAMs should continue to be studied by conservationists. Further research can examine the potential causes of the TAMs and prevention methods . Potential causes of TAMs I did not study include a virus, bacteria or fungal infection. To maintain the existence of this magnificent tree, conservationists should continue to work with research efforts and identify areas tree fitness can be improved. ACKNOWLEDGEMENTS A special thanks to Emilia Triana for helping me formulate my ideas and guiding me through the obstacles I faced . Thank you to Sof a Flores for reviewing my paper and helping my thought process along the way. Thank you to the dedicated staff at the Monteverde Institute, specifically Randy Chinchilla and Debra Hamilton for their advice, data, tools, access to the Crandell Reserve and en thusiasm for this project. A big thank you to Sam Coursen for helping me collect data despite the horseflies, rain and snakeinfested grass. Thanks to Dev Joslin and Frank Joyce for introducing me to O. montevedensis and supporting my pursuit of this proje ct. Thank you to Mauricio Ram rez and the Curi Cancha staff for allowing me to use the Reserve. Finally, a large thank you to the Cruz family for taking me into their home for the duration of my research. LITERATURE CITED Belsky AJ, Carson WP, Jensen CL, Fox GA. 1993. Overcompensation by plants: Herbivore optimization or red herring? Evolutionary Ecology [internet]. [cited 6 June 2018];7(1):109121. Burger J, Graves D, Angel P, Davis V, Zipper C. 2017. Chapter 2: The forestry reclamation approach. In: Adams, Mary Beth, ed. The Forestry Reclamation Approach: guide to successful reforestation of mined lands. Gen. Tech. Rep. NRS 169. Newtown Square, PA: U.S. Department of Agr iculture, Forest Service, Northern Research Station: 2 1 – 28. Clark DB, Clark DA. 1985. Seedling Dynamics of a Tropical Tree: Impacts of Herbivory and Meristem Damage. Ecology [internet]. [cited 6 June 2018]; 66(6):1884 1892.

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Apical meristem termination in Ocotea monteverdensis Bennett 11 Da Sil va JK , D a Trindade R , Moreira EC , Guilherme J, Maia S , Dosoky NS , Miller RS , Cseke LJ, Setzer WN. 2017. Chemical Diversity, Biological Activity, and Genetic Aspects of Three Ocotea Species from the Amazon. International Journal of Molecular Sciences [internet]. [cited 6 June 2018] 18(5): 1081. Dhileepan K, McFadyen R. 2001. Effects of gall damage by the introduced biocontrol agent Epiblema strenuana (Lep., Tortricidae) on the weed Parthenium hysterophorus (Asteraceae). Journal of Applied Entomology [intern8. Fay PA Throop HL . 1999. Effects of fire, browsers and gallers on New Jersey tea (Ceanothus herbaceous) growth and reproduction. American Midland Naturalist [internet]. [cite 6 June 2018]; 141:51–58. Fay PA, Throop HL. 2005. Branching responses in Silphium integrifolium (Asteraceae) following mechanical or gall damage to apical meristems and neighbor removal. American Journal of Botany [internet]. [cite 6 June];92(6):954959. Godoy C, Miranda X, Nishida K. 2005. Treehoppers of tropical America. Santo Domingo de Heredia, Costa Rica: Instituto Nacional de Biodiversidad, INBio. HoughGoldstein J. LaCoss S J. 2012. Interactive effects of light environment and herbivory on growth and productivity of an invasi ve annual vine, Persicaria perfoliate. ArthropodPlant Interactions [internet]. [cited 6 June 2018]; 6(1): 103 112. Available from https://doi.org/10.1007/s118290119158z Joslin JD, Haber WA, Hamilton D. 2013. Ocotea monteverdensis. The IUCN Red List of Threatened Species 2013: e.T48724260A48724329. http://dx.doi.org/10.2305/IUCN.UK.20132.RLTS.T48724260A48724329.en. Downloaded on 25 April 2018. Joslin, JD , Haber, WA, Hamilton D. 2018. Ocotea monteverdensis. The IUCN Red List of Threatened Species 2018. P ublication Pending. Neumann Cosel L, Zimmermann B, Hall JS , V an Breugel M, Elsenbeer H. 2011. Soil carbon dynamics under young tropical secondary forests on former pa stures —A case study from Panama. Forest Ecology and Management [internet]. [cited 6 June 2018]; 261(10):16251633. Sparks AN, Boethel DJ. 1987. Late season Damage to Soybeans by Threecornered Alfalfa Hopper (Homoptera: Membracidae) Adults and Nymphs. Journal of Economic Entomology [internet]. [cited 6 June 2018]; 80( 2):471–477. Available from: https://doi.org/10.1093/jee/80.2.471 Whitham TG, Mopper S. 1985. Chronic Herbivory: Impacts on Architecture and Sex Expression of Pinyon Pine . Science.;228(4703):10891091.

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Apical meristem termination in Ocotea monteverdensis Bennett 12 APPENDIX Appendix 1. TAM classifications Name Picture Complete TAM ( B urrowed) Burrow entrance and exit holes can be seen at the bottom and top left branch.

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Apical meristem termination in Ocotea monteverdensis Bennett 13 Complete TAM (Not Burrowed) No entrance or exit holes are visible. TAM was dissected to reveal that no burrowing took place. Partial TAM Second shoot from the right was the apical meristem, but died and part of it has been removed. Stubby TAM

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Apical meristem termination in Ocotea monteverdensis Bennett 14 A short stub is all that remains from the previous apical meristem . Bumpy TAM Stem appeared to have some woody structure growing on it; possibly a gall. A fter disection, no cavities for insects were found.

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Apical meristem termination in Ocotea monteverdensis Bennett 15 Appendix 2. Galls found on saplings. Name Picture Leaf Gall Three leaf galls pictured in one plant.

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Apical meristem termination in Ocotea monteverdensis Bennett 16 Trunk Gall and Branch Gall Trunk gall is large mass on vertical stem. Branch gall is the smaller cylindrical growth on the bottom horizontal branch. Note that in all other cases, branch galls occur on saplings without trunk galls.


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