The texts I will discuss were collected from the Minnamurra Rainforest, part of Budderoo National Park, New South Wales. The park contains a 1.6 km raised wooden walkway through the rainforest. The signs are placed on small extensions to the hand-rail of the walkway. The texts were photographed and transcribed in July 1997. For comparison, I will also discuss a small selection of signs collected at the Sydney Tropical Center Greenhouse, Sydney Botanical Gardens. These signs are also placed along a raised walkway, and were also collected in July 1997.

I will discuss the Rainforest texts as a whole, as if they were a single text, and I will also consider some of the signs individually. In particular, I will discuss how the texts treat the reader and the reader's participation in understanding the rainforest, how the texts present the rainforest and its parts, and how the texts move the reader from 'common sense' experiential observation to more specialized scientific understandings.

It is important to note that these small signs which were placed along the walkway at the rainforest park are only a subset of the texts displayed at the site. Some much longer texts are displayed at the Visitor's Center and at a look-out deck set off from the main walk-way called "The Out-door Classroom". Guided educational tours are also offered. Likewise, the three signs from the Sydney Tropical Center were chosen to provide contrast with the Rainforest signs, not to represent the use of text at the site as a whole. This paper should not be taken as a criticism of these texts, only as an investigation of their features.

Taken together, the text of the nineteen signs collected at the Minnamurra Rainforest can be divided into 128 clauses. Seventeen of the signs have titles consisting of one or two words. There are 106 major clauses, of which 14 are embedded and 92 are non-embedded clauses.

Clause Summary

The text of the Minnamurra Rainforest signs positions the reader as an active participant-observer. This is achieved by the reader's involvement in clauses in the role of Senser, the use of imperatives and interrogatives, and by the modality of the clauses in which the reader is involved.

Twenty clauses involve the reader either as a participant in a grammatical process, or/and as the object of an imperative. The texts collected contain twelve examples of signs which directly involve the reader in one of these two ways. Contrast this with the signs collected at the Sydney Tropical Center in which no clause involves the reader as a participant. The clause "Please do not touch" was the only example of an imperative that was found, and it is interesting that this was found on an informal, partly hand-written sign rather than the usual professionally designed one.

Clauses involving the reader as participant.

Imperative clauses

In the Rainforest signs which involve the reader as participant, the reader occurs seven times as Senser in Mental processes of Perception. These processes, however, also have a cognitive element. The reader not only "sees" as in "You might see eels or a fish", but also "spots" and differentiates different kinds of leaves, ferns and bark. The reader also notices lichen by its specific features, and observes the beginning and results of specific processes. This trend continues in the imperative clauses where the reader is instructed not only to look and listen, but to "Learn to recognize" and to "Compare". Clearly the reader is not merely being placed into the role of passive looker and listener, but also into that of a scientific observer and differentiator.

This is reinforced by the use of two WH-interrogatives, both asking "How many" different types or kinds of a feature the reader can observe. These are not merely rhetorical questions in which the reader knows that the writer of the text already knows the answer (c.f.: Lemke 1990: 9). Rather, readers are invited to actively investigate the Rainforest and find a new answer based on their own observation. The reader is invited to become a researcher. Contrast this with the polar question "Have you noticed..." which directs the reader explicitly to the target feature.

Notice also the modality of these clauses involving the reader. Two clauses directly express uncertainty about what the reader "might" see. This uncertainty also appears in "If you're lucky" and "Have you noticed...?" (Perhaps the reader has not.) Five other clauses refer to what the reader "can" see or observe. This modulation (Halliday 1984: 89) refers not only to readers' ability, but also to their possible inclination. It expresses a form of "deference politeness" (Scollon & Scollon 1983) in which the reader's action is not assumed. Compare this to an alternative with a different modal operator which allows no uncertainty or choice, such as "Along this section you will see..." The contrast is even stronger in the strictly Relational and Existential constructions of the "Schizaeaceae" sign. Here the reader's participation is irrelevant.

Modal Finites in clauses involving the reader as participant.

In the "Rainforest habits" sign there is another example of uncertainty. In this case, however, it is an example of uncertainty in interpretation on the part of the writer of the sign. "Buttresses appear to prop up the tree, but... || May contribute more to gas exchange in poorly drained soil." Such a non-categorical statement is highly uncharacteristic of science discourse (Lemke 1990: 130), of factual writing (Martin 1989:46), and of science exposition in particular (Martin 1993b: 197). The otherwise technical and nominalized style of the sign is under cut by the admission that the facts are uncertain, and that more than one interpretation is possible. Other examples are "They [the rocks] are believed to be 200 million years old" (Minnamurra), and "The diversity of species can be and indicator of the age of the rainforest" (Ferns). Taken together with the deference towards the reader's ability and inclination, and the two open information questions, these examples of uncertainty reinforce the construction of the reader as participant-observer. They put the reader's investigation and interpretation on a more equal footing with the expert writer(s) of the signs.

As would be expected, many clauses in the Rainforest text refer explicitly to the reader's immediate environment. However, the text does not only refers to things that the reader can see, it contextualizes the reader into the physical environment. The Rainforest signs have a sense of immediate place, and the reader is treated as part of that place.

In addition to the reader's role as Senser, some clauses and clause combinations add movement or direction to the process of perception. For example, the reader is instructed to "look up to" and to "look down at" parts of the environment, and to "Sit [here] quietly/ and listen" and "Turn around / and have a look... from another view". Two clauses involve the reader as an Actor in processes of Movement through the immediate environment (see table below), and many others refer to the immediate environment through Circumstances of location. Five Circumstances refer to the local geographical environment, and only one abstractly places an entity within "a process".

Circumstances of Location - immediate environment.

Circumstances of Location - geographical or abstract environment.

Contrast this with the Sydney Tropical Center signs where there is no reference to the immediate environment, and in some clauses even geographic distributions and the physical location of features is nominalized and abstracted. Note that the circumstance "under the microscope" does not refer to a physical location, but rather it refers metaphorically to the invisibly small scale of the feature. Except for the instruction "Please don't touch", the reader of the Tropical Center signs, could be anywhere - even reading from a text book in a far off location. The reader of the Rainforest text is treated as here and now, in the rainforest.

Abstract and nominalized Circumstances - "Schizaeaceae"

Many other clauses refer to the location of items or features in generalized processes. For example, the "Stranglers" signs and "Roots" explain the process of how stranglers and roots grow in the rainforest in general. Thus, circumstances such as "on a branch of another tree", "down the trunk of the host tree" and "on the ground surface" refer to these locations in general. At the same time, however, the signs refer to specific features of the forest that the reader can actually see. Thus, these locational circumstances have a double function, referring both to the general and the immediate. The reader is engaged in examining lichen, for example, both immediately as "the patchy green and white stains on some of the rocks and tree trunks" (Lichen), and in general as "the combination of moss and algae", and "the first evidence of the rainforest process" (Forest beginnings). The reader's presence and observation become a bridge back from the general process, to the specific, immediate, instance.

The construction of the reader as participant-observer, and use of the readers presence and observation in the explanation of generalized processes, are validations of the reader's experience and interpretation of the Rainforest. Rather than setting up a strict opposition between the reader's common sense, experiential, observation-based understanding, and the less immediately obvious and abstract scientific understanding of the Rainforest (Martin 1993b: 169), the text encourages and incorporates it. The science of the Rainforest becomes "an extension of common sense" rather than "an esoteric alternative" (Lemke 1990: 144). We now have a double contextualization: the reader into the immediate environment, and the reader's experience into the process of understanding the Rainforest.

The Minnamurra Rainforest is presented as dynamic. Things in the forest are presented in terms of what they do, rather than what they are or have, how they are used, or where they are distributed. The majority of clauses are dynamic and the majority of Actors in these Material processes are plants or parts of plants. Rainforest elements are described, classified and explained using embedded and nominalized processes, and also through longer clause sequence.

Looking at the process types in the Rainforest texts, we can see that almost 20% of the major clauses involve mental processes. These are the clauses involving the reader as participant-observer. Relational and Existential clauses make up 36%, and 46% are Material processes, of which only nine are rank-shifted to embedded clauses. It may seem natural that texts related to biology and ecology should contain a majority of dynamic material processes, however the "Schizaeaceae" sign from the Sydney Tropical center shows that this is not necessarily the case. This text contains no Mental processes, and only two Material processes, both of which are embedded. All the major clauses are Relational or existential.

Process types - Rainforest signs

Process types - "Schizaeaceae"

Not all Material clauses in the Rainforest text have an explicit Actor, however in those that do, the actor is usually a plant or a part of a plant. Aside from the reader, the only human Actors mentioned are the Aboriginal people who once lived in the area ("Minnamurra"). The rainforest is not being presented as a place where humans act other than as observers. In the case of "the Park's regeneration program" ("Regeneration"), it is clearly the plants which are actively reclaiming the space. Any use of the Rainforest as a resource, for logging ("The Survivor"), or even by the Aboriginal people, is firmly placed in the past. To put it bluntly, the Rainforest is a place to look but not touch. Contrast this with the "Theobroma cacao" sign at the Sydney Tropical Center where the plant is explicitly labeled an "Economic resource".

Types of Actors

Things in the Rainforest are often described in terms of what they do, or the part they play in processes. One strategy is to provide specification using an embedded process. This occurs five times in conjunction with an identifying relational clause (Martin 1993a: 149, 1993c: 225). For example, the lichen, which had previously been pointed out as "patchy green and white stains" (Lichen), is now defined in terms of its process of formation (c.f.: Martin 1993b: 179). Other participants such as Goals and Phenomena are also specified by their function or habits. Contrast this with the signs from the Sydney Tropical Center where items are described in terms of their distinctive physical features, place within the species, geographic distribution, or their uses.

Describing, classifying and defining things with embedded processes:

Another strategy is to insert a nominalized process into one of the Participant roles in a clause. Thus, the process of lichen formation on a rock identifies the beginning of "the rainforest process" (lichen), stinging plants are classified by the function of their hairs (Stinging plants), dense shade from the canopy is given the implication of limiting the growth of plants (Canopy), and buttress roots are implicated in the process of "gas exchange in poorly drained soils" (Rainforest habits). The nominalization of these processes allows them to participate with other rainforest elements and processes in a wide range of clause types and thus semantic patterns (Halliday 1993a).

Describing, classifying and defining things with nominalized processes:

On a larger scale, the roles played by elements of the rainforest are sometimes explained over the course of several clauses. They are "defined by enhancement" through "implication sequences" which explain their function or action. (Martin 1993a: 156). In the Canopy sign, for example, the canopy is pointed out, its functions in relation to light and climate are explained, and then implications are given for the forest floor. Likewise in the Stranglers sign, Stranglers are introduced, their growth pattern is explained chronologically through a sequence of Material clauses, and then an alternate scenario is given. Note that the motivating process that leads to its unusual form, "adaptation to low light levels" is given as part of the plant's definition. The clause structure reveals the steps of the implication sequence and the alternate scenario. Notice also how, in the alternate scenario clause complex, the established pattern of primary followed by secondary clause is reversed to place the condition for the alternate first.

Stranglers Sign: Text sections and clause combination

Martin (1993b: 169) notes that what are often referred to as common sense understandings are based on direct sensory observations. Common sense classification systems and explanations tend to be experiential and functional. Martin gives the example of a body-builder's informal taxonomy of muscles (1993a: 139). Scientific understandings, on the other hand, are based on less obvious factors. They are often based on criteria that are not immediately observable (perhaps requiring special instruments) and they comprise an alternate "thematic pattern" (Lemke 1990) of classifications, definitions and explanations. But rather than setting up an opposition between common sense and scientific understandings in which either one or the other is invalidated, both Martin and Lemke argue that common sense experience and observation can be the "starting point for learning science" (Martin 1993b: 170, see also Lemke 1990: 144).

We have already seen how the Rainforest texts position the reader as an active participant-observer, and how the reader's observations and interpretations are validated. This is the experiential common sense starting point. The scientific understanding that the texts move towards is that of the many interlocking processes that make up the rainforest. The reader moves from the obvious and immediate, differentiating the rainforest's elements, to an understanding of processes that are not immediately observable because they extend over time. Some signs begin with the reader's observation and move towards an explanation of processes and implications. Examples are Minnamurra, Canopy, Lichen and Regeneration. Others, Ferns for example, do the reverse. Still others simply point out specific instances of a general process. Examples are Epiphytes, Rainforest habits, Stranglers and Forest beginnings.

As each sign contextualizes an element of the rainforest into the processes in which it plays a part, the text as a whole builds up a thematic pattern in which the elements of the rainforest are linked by interacting processes. The canopy, for example "Blocks out 70 percent of the sunlight" and thus Epiphytes and Stranglers grow high on the branches of other trees to get closer to the light. It also creates the conditions for the forest floor, where roots have adapted by growing close to the surface, and contributing to gas exchange. Lichens begin the process of soil formation which creates the conditions for ferns and other plants. The diversity of these species indicates the age of the forest. The age of the forest can also be seen in the deep channel cut by the Minnamurra rivulet on its way to the sea. Each sign presents an aspect of the overall thematic pattern. As Lemke points out, it "it can be difficult or impossible to teach a thematic pattern one piece at a time because it often takes a mastery of the whole pattern before any of its parts seem to make sense." (1990: 17). The Rainforest texts make sense of "the parts" by contextualizing them into their environment and into wider processes. The complex relationships between processes are implied, but not explicitly set out in these small signs (c.f.: Lemke 1990: 22) Each sign provides a possible entry point through which readers can build up their understanding gradually and according to individual interest. The reader is not asked to master "a cluster of related concepts, all at the same time" (Halliday 1993b: 72). It would be interesting to examine how educational tour guides work in conjunction with the signs, and how they make connections between them.

The Rainforest texts position the reader as an active participant-observer. The reader is contextualized into the immediate environment, and the reader's observations and interpretations are contextualized into the process of understanding the Rainforest. The Rainforest itself is presented as dynamic, each element of the forest is contextualized into the processes in which it takes part, and these processes overlap and interact. Process, of course, implies continuity, and this is reinforced by signs such as Minnamurra and Minnamurra Rivulet which contextualize the forest into the geographical region and into geological time. Together, this presents a picture of the rainforest in which to damage any small part is to risk damaging the forest as a whole. If we dig up the Schizaeaceae plant at the Sydney Tropical Center, we remove a plant which has a certain set of features, but we do not remove a part of an integrated environment, or disrupt a set of continuously interacting processes. Once again, the rainforest is presented as a place to look and participate in understanding, but not touch.

Halliday, M.A.K. (1993a). "On the language of the physical sciences." In Writing science: Literacy and discursive power. Ed.: Halliday, M. A. K. & J. R. Martin. Pittsburgh: University of Pittsburgh press. Pages 54-68.

Halliday, M.A.K. (1993b). "Some grammatical problems in scientific English." In Writing science: Literacy and discursive power. Ed.: Halliday, M. A. K. & J. R. Martin. Pittsburgh: University of Pittsburgh press. Pages 69-85.

Halliday, M.A.K. (1994). Introduction to Functional Grammar. 2nd Edition. London: Edward Arnold.

Lemke, Jay L. 1990. Talking science : language, learning, and values. Norwood, N. J.: Ablex Publishing Corp.

Martin, J. R. (1985). Factual writing: Exploring and challenging social reality. Geelong, Victoria: Deakin University Press.

Martin, J. R. (1993a). "The discourse of geography: Ordering and explaining the experiential world." In Writing science: Literacy and discursive power. Ed.: Halliday, M. A. K. & J. R. Martin. Pittsburgh: University of Pittsburgh press. Pages 136-165.

Martin, J. R. (1993b). "Literacy in science: Learning to handle text as technology." In Writing science: Literacy and discursive power. Ed.: Halliday, M. A. K. & J. R. Martin. Pittsburgh: University of Pittsburgh press. Pages 166-202

Martin, J. R. (1993c). "Life as a noun: Arresting the universe in science and humanities." In Writing science: Literacy and discursive power. Ed.: Halliday, M. A. K. & J. R. Martin. Pittsburgh: University of Pittsburgh press. Pages 221-267.

Scollon, R. and S. Scollon. (1983)." Face in interethnic communication." In Richards, J. and R. Schmidt (eds.) Language and Communication. London: Longman.

Consider the age of these ancient river boulders. They are believed to be 200 million years old.

Some of these ancient rocks were used by the local Aboriginal people for making tools.

People from the Wadi Wadi tribe wandered along this river, often fishing for eels or collecting edible plants from the river banks.

Look into the deep water hole. Might see eels or a fish.

If you're lucky, you might see a water dragon sunning itself on a rock nearby.

[Picture: water dragon]

They use the tree for support only, not for food.

Their food is fallen leaves that get trapped in the plant.

Birds nest and Elkhorn ferns are familiar epiphytes.

Others are orchids, lichen and mosses.

How many different leaves can you spot on the ground around you?

[Pictures: Kinds of leaves]

Along this section of the walkway you can see five distinctive bark types.

Minnamurra Rainforest has over 90 species of ferns -- from tiny filmy ferns, maidenhair and bracken to giant tree ferns.

Two-thirds of the known fern species in New South Wales occur at Minnamurra.

The diversity of species can be an indicator of the age of the rainforest.

Strangler figs are the bizarre giants of the rainforest - an example of adaptation to low light levels.

Life begins when a seedling sprouts on a branch of another tree.

If the same seed had landed on the ground, it would have developed in the usual tree form.

[Picture: tree trunk]

Trunks are generally cylindrical, columnar and high branching…

Lower trunk may be fluted or buttressed….

Buttresses appear to prop up the tree, but…

May contribute more to gas exchange in poorly drained soil.

Rainforest trees have shallow roots.

Many go down less than a metre, and many are found on the ground surface.

The floor is the gate through which the forest's nutrients flow.

The roots grow where the food is available -- close to the surface.

We can observe the beginnings of the rainforest process on a rock.

Lichens on a once bare rock are the first evidence of the rainforest process. Then come mosses and creepers.

As they live and die, the mosses form soil for the ferns to grow. And so on.

Each plant takes its turn in the ongoing process of rock breakdown and soil creation.

Lichens are plants formed by the combination of fungus and algae.

They begin the process of breaking down the rocks to soil for other plants to grow.

Lichens are excellent pollution detectors because they survive only where the air is clean.

Some rainforest plants have stinging hairs to protect them from insect attacks.

Stinging nettle and this giant stinging tree are two types of stinging plants found in Minnamurra.

Protect yourself!

Learn to recognise these plants.

[Picture: leaves. Caption: large heart-shaped leaves of the giant stinging tree].

Two common weeds make regeneration of the rainforest difficult -- lantana (seen here) and mistflower (on the other side of the walkway).

You can see the results of the Park's regeneration program starting to have effect.

The small trees are beginning to create a canopy that will eventually shadow out the weeds, which need sunlight to grow.

The lantana is starting to retreat.

You are about to cross over the Minnamurra Rivulet., one of the few streams that flows over the Illawarra escarpment to the sea.

The force of the water has, over many thousands of years, cut the deep channels of this sheltered valley.

By the time the water reaches the coast, it flows more slowly and often floods.

Red cedars such as this were once extensively logged through out the Illawarra region.

This magnificent tree survived these impacts and is probably one of the oldest cedars in the park.

[Picture: leaf. Caption: Red cedar (Toona cilaita)].

[Picture: plants]

The family Schizaeaceae consists of four genera and around 140 species. Two genera occur in Australia and both Schizaea and the climbing fern Lygodium, occur in N.S.W. They may grow in the shade or in more open habitats. The family has a tropical and southern hemisphere warm temperate distribution. All genera have sporangia along leaf margins, but the location of the fertile parts of the fronds varies widely within the family . The frond lamina is usually pinnately or dichotomously compound. Under the microscope the sporangia are distinctive in that the annulus by which they open to shed the spores is in the terminal position.

Family: STERCULIACEAE

Economic resource plant.

Nepenthes have a passive trap system and do not close.

Touching or "feeding" pitchers will kill them.